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The damage caused by wind in middle-aged Scots pine stands on permanent thinning experimental plots

100%

Zachara T., Gil W.

Folia Forestalia Polonica. Series A . Forestry

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2021

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tom 63

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nr 4

2

Biomass of pine saw timber stands growing on the fresh mixed coniferous site

100%

Pilarek Z., Gornowicz R., Galazka S.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2007

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tom 06

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nr 2

3

Volume increment indexes and their variation in a 35-year old pine stand

100%

Turski M.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2006

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tom 05

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nr 2

4

A model describing forwarder based logging performance in pine stands thinnings

86%

Walczak M., Grodecki J.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2012

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tom 11

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nr 3

Logging is an important element of wood production. Its modelling gives an opportunity to compare different scenarios before the work has started and may be helpful in future operations planning. A computer program was created which includes basic factors influencing forwarder efficiency: parameters of the machine, the stand and the assortments. The results of the simulation confirm relations between certain factors and forwarder performance given by other authors. Counted absolute values may be higher than real. Relative comparison of relations between factors is more accurate.

5

Differentiation of tree diameters at strip roads in a young pine tree-stand

86%

Stempski W., Jablonski K.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2014

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tom 13

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nr 1

The investigation was conducted in a 32-year-old pine stand, growing on a fresh coniferous site in western Poland. The strip roads in the stand had been designed and cut along tree rows 5 years prior to the investigation. The analysis focused on trees growing at 12 strip roads, in 3-meter-wide stripes on both sides of the strip roads and in control zones, half-way between each two neighbouring strip roads. The trees growing on the stripes along the strip roads were divided into three zones corresponding to tree rows. The first zone (I) was formed by trees growing in the row directly at the strip roads, while the zones two (zone II) and three (zone III) were formed by trees growing in the second and third rows of trees away from the strip roads, respectively, on both sides of the strip roads. The average distances of the zones two and three from the strip roads were 1.5 and 3 m, respectively. The diameters at breast height (DBH) of all the trees growing in the respective zones were measured. Moreover, the widths of the strip roads were measured, which resulted in dividing the strip roads into two groups: the wider strip roads (average width 3.6 m) and the narrower ones (average width 2.9 m). The statistical analysis showed significant differences in DBH values between the analysed zones, for nine of the strip roads. Both in the case of the wider strip roads, as well as in the case of the narrower ones, the trees growing directly along the strip roads were usually thicker than the more distant trees. A statistically significant difference between the DBH values of trees from zone I and II was found for one strip road. In most cases the trees from zone I were statistically thicker than the trees growing in the control zone.

6

Classical and order statistics of effective active time of felling at use chainsaw

86%

Glazar K., Bocianowski J.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2012

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tom 11

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nr 2

The time, within which accordingly to its application machine works, and an object of work and working groups are under load,is the effective active time. The purpose of the research was the classical and order statistics of effective active time of felling at use chainsaw. The average effective active time of felling of one tree was about 2 s. The cut trees were strong statistical diversified from the point of view of effective active time of felling. The positive skewness coefficient has confirmed, that statistical units with value of feature below arithmetic mean were prevailed – right-sided asymmetry.

7

Health condition and structure of pine stands on permanent experimental plots in the Kwidzyn Forest Division

86%

Beker C., Wudarczyk M.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2007

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tom 06

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nr 4

The study presents the health condition and structure of pine stands growing on permanent experimental plots in the Kwidzyn Forest Division, the Ryjewo working circle, the Lisewo Forest District. Forest mensuration analyses were performed in a 127-year old pine stand (compartment 214), in five plots of 0.26 ha each. The health condition of the stand was determined on the basis of the losses of the assimilatory organs, i.e. defoliation. Mean defoliation of tree crowns was 20.3% (below the warning level), which corresponds to the damage rate of 1.14. A vast majority, i.e. 67% of the 176 analysed trees, represented damage rate 1 (Table 2). Taking into consideration the age of the stand (127 years) and its provenance (it was planted on former farmland) the health condition may be considered good. The structure of social classes of tree position in the stand shows an appropriate share of the upper storey (81.2-95.1%) and the second storey (4.9-18.8%). When analysing the basic characteristics of the stand structure it was found that the biggest variation was observed in crown length (from 17% to 30%), while the smallest – in height (from 6% to 9%). The mean relative crown length in the stands ranged from 0.21 to 0.24. Tree slenderness, defining resistance of trees to damage caused by wind and snow took mean values below 1.0 (from 0.71 to 0.83). This shows good stability of the analysed stands. Those stands are characterized by high yields of 465-614 m3 large timber per 1 ha and stocking of 1.0 to 1.3. As a result of the analyses of the interdependencies between the basic mensuration characteristics the most significant relationship was found for diameter at breast height and slenderness (from –0.718 to –0.913), height and absolute crown length (0.619-0.715) and diameter at breast height and height (0.161-0.708; Table 4). The trends in the annual increment in diameter at breast height showed the biggest decreases in the years 1977-1983, 1969-1974, 1962-1967, 1956-1960 and 1949-1952 (Fig. 6). Those periods coincide with gradations of nun moths and adverse weather conditions.

8

Effective active time of limbing and conversion at chainsaw use in selected technology and habitat variants

86%

Glazar K.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2014

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tom 13

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nr 2

The time within which, accordingly to its application, machine works, and an object of work and working groups are under load, is the effective active time. The purpose of the research was the order statistics of effective active time of limbing and conversion at chainsaw use in two technology and two habitat variants. The effective active time of limbing and conversion of one tree was most frequently from 0.5 s to 10.49 s in variant in which the limbing included tree crowns and only thicker branches cutting and the conversion included rods meant for chipping. The strong tree’s branching in fresh mixed coniferous forest had influence on the prolonged limbing time. The share of S2a assortment in total volume of harvested wood had influence on the conversion time, besides the number of wood assortment cutting.

9

Order statistics of effective active time of limbing and conversion at use chainsaw

86%

Glazar K.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2013

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tom 12

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nr 1

The time within which, accordingly to its application, machine works, and an object of work and working groups are under load, is the effective active time. The purpose of the research was the order statistics of effective active time of limbing and conversion at chainsaw use. The removed trees were moderately diversified from the point of view of effective active time of limbing and conversion. The negative skewness coefficient qualified the distribution of effective active time of limbing and conversion as weak left-side asymmetry in variant 1 (the limbing included cutting of trees’ crowns and all branches). The positive skewness coefficient qualified the distribution of effective active time of limbing and conversion as weak right-side asymmetry in variant 2 (limbing included cutting of tree crowns and only thicker branches).

10

Analysis of covariance of height of pine stands

86%

Kazmierczak K., Graczyk M., Zawieja B.

Colloquium Biometricum

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2008

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tom 38

11

Volume increment indices of 5-year increment periods and their variability in the 86-year old pine stand

86%

Turski M.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2005

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tom 04

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nr 1

12

Diameter growth rate of pine stands in the Swierklaniec chief forestry

86%

Rymer-Dudzinska T.

Annals of Warsaw Agricultural University. Forestry and Wood Technology

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1992

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tom 43

13

A boreal-temperate transect in Europe: history of pine stands reconstructed from the radial growth of trees

86%

Parn H.

Polish Journal of Ecology

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2003

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tom 51

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nr 4

History of the Scots pine sites along the Finland-Poland boreal-temperate transect along 25°E longitude, ranging from 50°N-70°N latitude (see Fig. 1 in Breymeyer 2003) was reconstructed using tree-rings. The correlation between the tree-ring index chronologies for the sites was studied. The age of trees at particular sites varies in the range from 66 to 178 years. The youngest trees are growing at the sites FN3 and PL3, the eldest at FN1. At the sites FN1 and PL1, two groups of trees of different age were separated. Correlation analysis revealed significant correlation among the Baltic chronologies. High correlation coefficients were also found between the PL2 site chronology and all the Baltic state chronologies. No positive correlation was detected among the chronologies from the sites in Finland and in Poland.

14

Social structure of pine stands being under the influence of industrial emissions

86%

Michalak K.

Annals of Warsaw Agricultural University. Forestry and Wood Technology

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1992

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tom 43

15

The operative labour consumption of technologies of fuel wood harvesting from improvement cuttings in pine stands

86%

Maciejewska K.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2005

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tom 04

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nr 1

16

Damage to trees and regeneration layer resulting from timber harvesting with the use of equipment aggregated with farm tractors in thinned pine stands

72%

Stanczykiewicz A., Sowa J. M., Kulak D., Leszczynski K., Szewczyk G.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2012

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tom 11

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nr 2

The research was conducted in pine stands where selective early and late thinning was carried out with the use of NIAB 5-15 and HYPRO 450 debranching and cutting processors along with a FRANSGÅRD V-6000 GS cable winch aggregated with farm tractors. In case of cut-to-length system, timber harvesting was executed by means of processors and in case of tree-length system – by means of a cable winch. The harvested timber was forwarded to the depots in the second stage with the use of self-loading trailers or skidded with the use of a cable winch. Tree damage in case of processor technology oscillated at the level of 3.1-11.3%, and in case of a cable winch: 3.0-10.9%. The level of damage to the regeneration layer amounted to 4.1-27.1% for the areas where processors had been used. For the areas where timber was harvested by means of a cable winch, the level of tree damage was 5.2 -14.0% of trees growing under the main stand’s crown layer.

17

Age-related changes in leaf area index of young Scots pine stands

72%

Jagodzinski A. M., Kalucka I.

Dendrobiology

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2008

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tom 59

57-65

We studied the chronosequence of six Scots pine (Pinus sylvestris L.) plantations (6-, 9-, 11-, 15-, 17-, and 20-years-old) to examine the changes in leaf area index (LAI) over stand age. The study site was located on a mine spoil heap (outer dumping ground) in the Belchatow lignite open-cast mining district (central Poland). The main goal of the study was to analyze LAI changes over stand age in a chronosequence of young Scots pine stands and to test the relationship between LAI estimates derived from a LAI-2000 Plant Canopy Analyzer and site-specific allometric equations. In addition, we tried to determine whether LAI estimated by a LAI-2000 PCA can be used to accurately estimate forest biomass. We hypothesized that LAI-2000 PCA underestimates LAI of the stands, and that stand age (and linked stand parameters) may influence the range of the hypothetical underestimation due to changes in biomass allocation. Our study revealed that LAI was highly dependent upon stand age and tree density (p<0.0001) regardless of the way how LAI was determined. Moreover, we found that LAI estimated by LAI-2000 PCA significantly correlates with stand biomass per area; the highest coefficients of determination were found for total aboveground biomass, aboveground woody biomass, and stem biomass. This means that data obtained by LAI-2000 PCA are good predictors of stand biomass in the young stages of stand development. In contrast to our prior assumption, the results showed that LAI-2000 PCA overestimates leaf area index. The relative differences between the values obtained with LAI-2000 and those calculated on the basis of the site-specific allometric equations increase with age. This may reflect changes in crown architecture over age caused by enlarging tree dimensions and over - crowding of trees leading to deterioration of light conditions inside the canopy.

18

Ecological aspects of wood harvesting and skidding in pine stands with use different technologies

72%

Glazar K., Maciejewska M.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2009

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tom 08

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nr 3

The new look at the forest economy takes into considerationmaximum protection of forest ecosystems, first of all. The purpose of the research was to estimate the influence of wood harvesting and skidding technologies on forest environment, particularly on soil and remained stand. The traditional wood harvesting and skidding technology (compact sawing machine, tractor with winch) was more friendly for soil environment than the newest technology (harwarder). Decrease of the negative influence of engineering wood harvesting and skidding process on forest environment is possible through application of both technologies and technical means correctly selected for the purpose. Besides, the operator’s practice is of a significant meaning.

19

The analysis of the volume of logging residue in final fellings in pine stands

72%

Chlebowski K.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2007

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tom 06

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nr 4

The aim of the work was to determine which part of biomass remains in the forest in the form of so-called logging residue. In order to achieve the result, the analysis of wood volume harvested in the final felling was carried out, and the total volume was broken down into different parts of trees. Furthermore, to estimate the wood volume of the forest stand, on each of the experimental plots 10 model trees were chosen based on Draudt method. Assuming that the thickness of wood acquired from forest is bigger than 4 cm, it is possible to assume that the part of biomass which remains in the forest in the form of the branches and conifer needles ranges from 10% to 12% of general amount of biomass.

20

Spatial pattern of trees of different diameter classes in managed pine stands (Pinus sylvestris L.) of different age

72%

Szmyt J.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2010

|

tom 09

|

nr 3-4

The present research was conducted in managed stands of Scots pine (Pinus sylvestris L.) at different age in Poland. All the investigated stands were planted and thinned according to selection thinning. Analysis of spatial structure concerned trees of different categories (DBH classess) depending on the age of stand. Spatial distribution of trees was investigated using two commonly used methods: Clark-Evans R index and Ripley's L(t) function. In stands of age 43 and 65 the effect of the initial spacing was observed and all living trees were distributed regularly at the smallest distances and at larger spatial scale they were spaced randomly. Random type of spatial structure of trees was observed when smaller and larger trees were taken into consideration, separately. In case of stands at the age 90 the effect of the initial planting on the spatial structure of trees was not observed even at the smallest distances independently of the category of trees taken into account. All living trees in these stands were distributed randomly. Only in two stands clumps of trees were observed and one concerned smaller trees and the other - larger trees. Size differentiation index was small for all stands. The lowest values was ascertained in the oldest stands.

Ograniczanie wyników

The damage caused by wind in middle-aged Scots pine stands on permanent thinning experimental plots

Biomass of pine saw timber stands growing on the fresh mixed coniferous site

Volume increment indexes and their variation in a 35-year old pine stand

A model describing forwarder based logging performance in pine stands thinnings

Differentiation of tree diameters at strip roads in a young pine tree-stand

Classical and order statistics of effective active time of felling at use chainsaw

Health condition and structure of pine stands on permanent experimental plots in the Kwidzyn Forest Division

Effective active time of limbing and conversion at chainsaw use in selected technology and habitat variants

Order statistics of effective active time of limbing and conversion at use chainsaw

Analysis of covariance of height of pine stands

Volume increment indices of 5-year increment periods and their variability in the 86-year old pine stand

Diameter growth rate of pine stands in the Swierklaniec chief forestry

A boreal-temperate transect in Europe: history of pine stands reconstructed from the radial growth of trees

Social structure of pine stands being under the influence of industrial emissions

The operative labour consumption of technologies of fuel wood harvesting from improvement cuttings in pine stands

Damage to trees and regeneration layer resulting from timber harvesting with the use of equipment aggregated with farm tractors in thinned pine stands

Age-related changes in leaf area index of young Scots pine stands

Ecological aspects of wood harvesting and skidding in pine stands with use different technologies

The analysis of the volume of logging residue in final fellings in pine stands

Spatial pattern of trees of different diameter classes in managed pine stands (Pinus sylvestris L.) of different age