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1
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Przyczyny krótkookresowych reakcji przyrostowych sosen z różnych siedlisk

100%
Wilczynski S.
Sylwan
|
2013
|
tom 157
|
nr 09
In homogeneous climate conditions Scots pine trees at different sites have similar short−term incremental rhythm. It was determined by the temperature of early spring and precipitation in June. Differences in the growth pattern are caused by various sensitivities of pines from different habitats to the temperature in May and precipitation in February and April of the current year.
2
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Wpływ trzebieży na przyrost radialny dębu w Nadleśnictwie Międzyrzec

100%
Sacewicz W., Bijak S.
Sylwan
|
2019
|
tom 163
|
nr 08
The intermediate cuttings have an important impact on the stand structure and productivity. Choosing the right method of the treatment performance is the decision, which is fundamental in shaping tree stands stability. The radial increment, apart from the natural growth potential of particular species, is influenced by many abiotic, biotic and anthropogenic factors, among which one can distinguish those that influence it directly, e.g. thinning. The study objective was to determine the effect of silvicultural treatments on the increment reaction of oak (Quercus sp.) stands in the Międzyrzec Forest District (eastern Poland). The empirical material was collected in six forest stands located in the Witoroż forest range. In each stand we cored 10 dominant and co−dominant trees (representing 1st and 2(sup)nd Kraft’s biosocial classes). After the measurements of the tree−ring widths and the synchronization of incremental series, the raw and standard chronologies were elaborated for each stand. In total, we analysed 8 treatments: six early and one late selection thinnings, and one late salvage thinning (tab. 1). For each treatment, three− and five−years’ value of mean tree−ring width was calculated for the period before and after the cut. Additionally, we calculated the incremental response parameters: recovery (Rc), resilience (Rs) and resistance (Rt) indices. For the majority of the analysed treatments, the cuts resulted in an increase in average tree−ring width both in the 3−, and 5−years perspective. However, statistically significant changes in this parameter occurred only in a few cases (fig. 2). The average values of incremental response indicators show that the investigated oak stands are characterized by a significant adaptive capacity and a rapid recovery of incremental capacity in the analysed time spans. At the same time, the low values of Rt index suggest that their growth resistance to disturbance caused by the thinning is rather low. The age of the stand at the time of the treatment significantly affected the incremental response parameters of the examined oaks. The older the stand, the incremental response was less intense.
3
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Stopień uszkodzenia drzewostanów świerkowych Gór Sowich

100%
Dmyterko E., Kluzinski L., Bruchwald A.
Sylwan
|
2014
|
tom 158
|
nr 03
The aim of the research was to assess the degree of damage to spruce trees and stands and to study their growth responses to the changing environmental conditions in the Sowie Mountains (Central Sudety Mts.). To assess the degree of damage to trees, three methods based on crown characteristics were used. The types of growth responses of trees to changing environmental conditions were additionally taken into account in one of the methods. Regardless of the assessment method, spruce stands in the Sowie Mountains demonstrated a high level of damage. The poorest growth conditions were found in the period 1966−1980 when a large number of trees showed negative growth responses, indicating a decrease in radial increment. The period 1996−2010 showed an improvement in the growth conditions of trees because the proportion of trees with negative growth responses decreased, while the proportion of trees with positive growth responses increased. It was also found that the growth conditions for spruce were more favourable in the lower montane forest zone (above 600 m a.s.l.), and less favourable at the foothills (below 600 m a.s.l.), which may be caused by the competition of beech replacing spruce in the lower locations in the mountains.
4
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Sygnal klimatyczny w slojach Picea sitchensis [Bong.] Carr. oraz Pseudotsuga menziesii [Mirb.] Franco

100%
Feliksik E., Wilczynski S.
Sylwan
|
2008
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tom 152
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nr 06
3-13
5
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Reakcja przyrostowa drzewostanów bukowych w Nadleśnictwie Cewice na zabiegi hodowlane

100%
Bijak S., Madrzak P.
Studia i Materiały Centrum Edukacji Przyrodniczo-Leśnej
|
2016
|
tom 18
|
nr 3[48]
6
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Reakcja przyrostowa jodły (Abies alba Mill.) na zmiany środowiska w powiązaniu z koroną wtórną

100%
Dmyterko E.
Sylwan
|
2014
|
tom 158
|
nr 02
The study concerns the secondary sunny crown of silver fir trees, its length and density as well as the relationship between the length of primary and secondary crown between the radial increment and secondary crown characteristics. It also discusses the importance of secondary crown in the life and population growth of silver fir.
7
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Stopień uszkodzenia drzewostanów jodłowych Beskidu Niskiego

100%
Dmyterko E., Bruchwald A.
Sylwan
|
2015
|
tom 159
|
nr 11
The main aim of the research was to study trees growth responses to the changing environmental conditions and to assess the degree of damage to trees taking into consideration their secondary crown. Based the material from plots established in 12 silver fir stands (tab.), chronologies were developed for trees in various age classes (fig. 1). 1950 saw a downward trend in the radial growth that continued till 1985, to be followed by an upturn lasting till 2000, when the radial growth stabilised. No significant changes in tree−growth were observed in the group of the youngest trees. Three types of growth response to environmental changes (positive, neutral and negative) were distinguished in the last three 15−year−long periods. In years 1970−1984 the largest proportion of firs indicated negative growth responses, while firs with positive response dominated in the period 2000−2014 (fig. 2). The period 1970−2014 saw a steady increase in the mean value of growth responses. The assessment of the top−crown growth (feature B) showed that more than 50% of the trees showed inhibited growth (fig. 3). The assessment of tree vitality (feature C) confirmed the dominance of trees with moderate crown vitality. The vitality of the secondary crowns (Zw) situated below the primary crowns (Zp) of firs was assessed on the basis of crown density and its length (formula [1]). Incorporating Zw in the assessment of tree damage (formula [2]) resulted in an increase in the vitality of the whole crown (Z) (fig. 4). Based on the defoliation, 73% of trees were found to be within damage class 2 (fig. 5). Another method of damage to trees determination was adopted (formula [3]) to assess the damage to fir stands and showed that the largest proportion of trees was with moderate damage (fig. 6). The damage index values obtained with this method were lower compared to the method that considers the defoliation exclusively. Even lower index values were obtained while using the method based on both damage index W and tree−growth response. Of the three discussed damage assessment methods, the most accurate is the method based on damage index Wz, taking into account the growth response of the entire crown (Z).
8
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Klimatyczne przyczyny krótkookresowych reakcji przyrostowych jodły pospolitej z pogórza oraz regla dolnego

80%
Wilczynski S., Szymanski N., Kolbut L.
Sylwan
|
2015
|
tom 159
|
nr 05
The aim of this study was to i) determine similarities and differences in the increment reaction of silver firs growing at different elevation, ii) identify climatic factors, which caused these response, and iii) determine dendroclimatic zones and identify a site, where a tree grew on the basis of tree−ring widths series. Studied stands were located in the Ustroń Forest District at the elevation of: 500−550 m a.s.l. (foothill zone, 18°59 E, 49°43 N) and 800−850 m a.s.l. (lower montane forest zone, 18°58 E, 49°43 N). In each stand 20 dominant firs were selected and one increment core per tree was taken. Tree−ring widths (fig. 1) were transformed into annual sensitivity index (fig. 2). Principal component analysis was used to reduce a number of original variables and classify the tree−ring series. Response function analysis was used to determine climate−radial increment relationships. The standardized series of firs on both sites were different in terms of the climate influence (fig. 3). The analysed trees responded differently to solar and thermal conditions in previous autumn and current summer as well as to pluvial conditions at the beginning of winter and in the second half of summer. The investigated firs had also common increment characteristics. The trees from both sites responded similarly to thermal, solar and pluvial conditions in February, solar and pluvial conditions in May and temperature in winter and summer (fig. 4). Climatic signal of each elevation zone was recorded by each tree and depended on the climatic conditions in given area. On the basis of standardized tree−ring series, dendroclimatic regionalization can be created and the stand, where a tree grew, can be identified.
9
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Krótkookresowe reakcje przyrostowe jodły, świerka i sosny rosnących w jednorodnych warunkach siedliskowych

80%
Wilczynski S.
Sylwan
|
2013
|
tom 157
|
nr 06
Study was performed in multi−species stand located in the Świętokrzyski National Park (central Poland). Silver fir, Norway spruce and Scots pine trees that grew in a uniform habitat conditions were selected. The trees showed the differences and similarities of changes of the size of radial increment, which result from species−specific sensitivity to selected meteorological elements
10
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Stopień uszkodzenia drzewostanów bukowych Ziemi Kłodzkiej

80%
Dmyterko E.
Sylwan
|
2017
|
tom 161
|
nr 05
The study presents the assessment of damage to beech stands using four methods, including that taking into account the radial increment. The condition of stands in 2016, and the growth response of trees to the environmental changes since 1956 are described. The measurements and observations were carried out on 18 sample plots (tab. 1) located in south−western Poland. The mean defoliation accounts for 32.5% ranging from 16.9 to 56.9%, while the average defoliation class value is 1.62 ranging from 0.75 to 2.38. The proportion of trees was found to be the highest (approx. 60%) in class of moderate damage (fig. 1a). The mean value of vitality is 1.17 (ranging from 0.75 to 2.38). The proportion of trees in vitality classes differs significantly from that in defoliation classes. The highest number of trees (approx. 80%) was found to be within damage class of weakened trees (fig. 1b). The assessment of damage to trees based on synthetic damage index (defoliation and vitality combined using formula [1]) is similar to the assessment method based on tree vitality. The mean value is 1.07, ranging from 0.63 to 1.70. The largest proportion of trees (over 80%) was found to be within class 1 (fig. 1c). The index SynZ combines defoliation and vitality, as well as the growth response of trees over the last 15 years according to formula [2]. Its values range from 0.82 to 1.79 with 1.21 on average. The largest proportion of trees (over 70%) was found to be within damage class 1 (fig. 1d). The response of trees to environmental changes is an important indicator of the growth conditions. The proportion of trees with negative growth responses increases from period to period, while the proportion of trees with neutral and positive responses decreases (fig. 2). The analysed beech stands show fairly large differences in the level of the damage. The most likely cause of this situation are droughts occurring in recent growing seasons, especially in 2012. Of the methods deployed to assess damage to beech trees, the morphological−growth one is the most accurate, but the most laborious. Therefore, it is preferable to use a synthetic damage index as both tree defoliation and vitality can also be assessed outside the growing season.
11
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Zastosowanie metod dendrochronologicznych oraz spektrometrycznych w monitorowaniu drzewostanów sosnowych na obszarach przemysłowych

80%
Sensula B. M., Wilczynski S., Piotrowska N.
Sylwan
|
2016
|
tom 160
|
nr 09
The main aim of this study was to analyze the variability of width as well as content of stable oxygen and carbon isotopes, and radiocarbon in Pinus sylvestris L. tree rings. Analysed Scots pine stand grew on the fresh mixed coniferous forest habitat type on site located in the vicinity of the power plant in Łaziska Górne (southern Poland). The combined usage of tree ring width and isotopic data allowed to identify how investigated trees have adapted to the pollution. Strong increase of industrial pollution emission was noted on the investigated site between 1960s and 1980s. During that time, the trees reduced their radial incement and the heterogeneity of their reaction increased, whereas their sensitivity to short−term impulses to changes in the environment conditions weakened. We observed depletion rates of 14C and δ13C concentration in α−cellulose related to the CO2 emission into the atmosphere in the processes associated with the fossil fuels combustion. Prior to 2000, a decrease in stomatal conductivity was associated with a minor changes in the net photosynthesis rate and that elevated CO2 increased intrinsic water use efficiency (approximately by 40%).
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