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The study examined the sensitivity to air temperature and precipitation of 18 Scots pine stands growing at dry and boggy coniferous forest habitats in Białowieska (BIA), Świętokrzyska (SWI) and Solska (SOL) Primeval Forests. At each plot, 20 healthy and undamaged pine trees were sampled (two cores per tree). The cores were scanned and the CooRecorder & CDendro 7.8 image analysis software was used for measuring tree−ring widths. The standardization of the individual tree−ring series for removing no−climatic variations was employed. For each stand the index chronology was constructed on the basis of individual index series. The grouping of site chronologies was performed by the cluster analysis. The principal components analysis was applied to identify common characteristics of chronologies. Correlation analysis was used in order to identify the climatic elements described by the main components. The first component (PC1) highlighted the variability common to all chronologies and described the average air temperature in February, March and May, and the total precipitation in June and July in the year of tree−ring formation. Regardless of the region and the site habitat, pines increased the radial increment when winter was warm and short, spring was cold and summer was abundant in precipitation. The PC3 distinguished pines growing in BIA. Scots pine increased radial growth when it was cold in June. The PC2 described climatic elements whose influence on the radial growth of Scots pine in both habitats was different. Therefore, the PC2 indicates that the pines from BIA growing at boggy and dry habitats reacted differently to precipitation in February and April. The pines at both these habitats in SOL differed in sensitivity to precipitation in February, May and August, while the trees in SWI only to precipitation in February. The results indicate that differences in climatic conditions between the regions were reflected in the size of the wood formed by the trees. On the other hand, site conditions modify significantly these relations. Therefore, due to the wide geographical range and habitats occupied by Scots pine, the climate−radial increment relationships should be analyzed in detail in any case.
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.
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
Sylwan
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2003
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tom 147
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nr 12
27-35
The aim of the study was to investigate how industrial pollutants and change of thermal conditions of winter season in the second half of the 20th century affected the basal area increment (BAI) and the climatic signal in the BAI chronologies of Pinus sylvestris and Pinus banksiana. Samples were collected from 21 trees of both species growing in the Chrzanów Forest District (50°20‵ N, 19°47‵ E) which is located between the Upper Silesian and Krakow Industrial Regions. Two cores were taken from each tree. Tree−ring widths were measured at the cores and the BAI for each year in the period 1930−2016 was calculated. The growth reductions of both pine species in the years 1951−1970, increasing of diversity of growth reactions from year to year and also reduction of strength of climatic signal in the period 1963−1994 may have been caused by industry pollution. The reduction of wood growth, the increase of the diversity of short−term incremental reactions and also the reduction of strength of the climatic signal were greater in Jack pine. This indicates that Scots pine was more resistant to pollution. As an industrial production declined and environmentally friendly technologies were introduced in the 1990s homogeneity of growth reactions and strength of dependence between BAI and climate parameters in both species increased. A significant increase in the strength of the relationship between January temperature and BAI of Scots pine and Jack pine was observed in the early 2000s. This may suggest that the vegetation season starts already in January in the study area.
Scots pine in the Polish part of the Carpathians shows a diversified annual rhythm of changes in size of the radial increments. It mainly results from a different susceptibility of trees to pluvial conditions of summer (June-August) and the air temperature during the autumn (October) preceding the year in which the annual tree ring is formed. The air temperature in the winter months (February-March) is the factor having the strongest effect on the variation of the increment rhythm of Scots pine growing in the entire area of the Polish Carpathians. The regions in which Scots pine exhibits a homogeneous rhythm of changes in the annual ring size have been named the dendroclimatic regions. They coincide with the physic-geographical and climatic regions. Pines in respective dendroclimatic regions of the Carpathians form a specific "climatype" distinguished by a different increment rhythm adapted to climatic conditions prevailing in a given area.
12
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Temperatura w profilu pionowym drzewostanu

63%
17
63%
The frequency of site and zonal pointer years in Norway spruce in two altitudinal zones (500−900 m and 900−1370 m a.s.l.) in the Western Beskidy Mountains was analysed. In total, 32 tree stands were studied – 16 in each zone. In both zones number of negative site pointer years increased along with increase of number of positive site pointer years. Above 900 m a. s. l. number of site pointer years increased along with the altitude, while below 900 m a.s.l. their number decreased along with the altitude. We found no common pointer years for all 32 populations. In lower zone, short winter, early and very warm spring or high precipitation in June and July in a given year caused negative pointer years. In the upper one positive pointer years occurred after the warm autumn and in years with the warm growing season.
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