1,720,976 research outputs found
Norway spruce (Picea abies L.) evidencing 370 years form “Torfowisko pod Małym Śnieżnikiem” in the Sudetes, Poland
No full textThe Śnieżnik Massif, with its highest peak, 1,425 m a.s.l., is located in the eastern part of the Sudetes, a mountain range running along the border of southwestern Poland and the northeastern part of the Czech Republic. It forms one of the highest parts of the Sudetes, distinguished by its partial elevation above the upper forest line. The research area is a small mire, called "Torfowisko pod Małym Śnieżnikiem" (50º11'47"N, 16º49'17"E). The mire covers a flat summit surface, located at an altitude of ~1,245 m a.s.l, approximately 600 m ENE from the culmination of Mt Mały Śnieżnik (1,326 m). At the top, but also in the middle of the slope, there are numerous flattened areas that favoured the formation of peat bogs. The maximum observed thickness of peat covers at the pass below the Mały Śnieżnik peak is lower than 75 cm, and most frequently reaches about 50-60 cm. The highest parts of the Śnieżnik Massif are covered with a Norway spruce (Picea abies) forest of the upper mountain forest zone. The trees are distinctive due to the frequent occurrence of broken tops caused by strong wind and weight of the ice and snow caps in winter. Fieldwork was performed in two campaigns in 2023: in early June and late July. Tree ring width (TRW) was measured under a stereoscopic microscope to 0.01 mm using LBD_Measure software (version 1.0). Tree ring width measurements from sample TM15 yielded 370 tree rings in the radius r1 and 370 tree rings in the radius r2 (counting from the same tree ring adjacent to the pith, to the bark). Thus, the sequence can be dated to the period 1653–2022. The spruce from which the sample originated is growing at an altitude of 1251 m above sea level in the central part of the mire “Torfowisko pod Małym Śnieżnikiem” (50.1960601N, 16.8212750E). It is 14.5 m high, and its DBH equals 31 cm. The average tree ring width of the TM15 spruce equaled 0.34 mm/year for the radius r1, and 0.31 mm/year for the radius r2 (on average 0.33 mm/year for TM15). Numerous tree rings are very narrow, i.e., 0.06 mm (3–4 rows of cells), and the widest tree rings reach 1.38 mm/year for r1 and 0.93 mm/year for r2. The period 1653-1771 displays rather variable tree ring widths. On several occasions tree ring widths exceed 0.8 mm/year (on average 0.44 mm/year). From 1742 to 1943, the selected tree TM15 has very narrow tree rings – on average 0.19 mm/year and there is little variability in tree ring width (below 0.5 mm). In the period 1944–2023, the tree ring width increases again to an average of 0.54 mm/year, and displays strong variability. An increasing trend in tree ring width is observed in the period 1944–1975, and a decreasing trend in tree ring width is observed in the period 1976–2023.Tree-ring width of oldest Norway spruce (Picea abies L.) in “Torfowisko pod Małym Śnieżnikiem”; 1st column - year, 2nd column - tree-ring width in mm.</p
Regional oak chronology QUSP_WP (spans 458 years), Western Pomerania, Poland
No full textWestern Pomerania is located in the northwestern part of Poland. It is bordered by the Baltic Sea to the north, and by Germany to the west, across the Odra River. It is a young glacial area that was occupied by ice sheets several times during the last 100 thousand years. The last glaciation took place about 22 thousand years ago, and the ice sheet retreated about 14 thousand years ago. Terrain forms that resulted from ice sheet melting are well-preserved in the surface relief and form a typical post-glacial landscape with numerous lakes, frontal moraine belts, outwash plains, plateaux, kame terraces and eskers. The bedrock is dominated by tills, fluvioglacial sediments and ice-dammed lake clays. Some sediments (mostly in ice marginal valleys) have undergone aeolian transport and now form extensive dune fields The studied oak trees are growing in fresh mixed forests and fresh forests, on cambisols and chromisols, often in multi-species forests. The oldest trees (>400 years old) are growing on the Wolin Island (northern part of the study area), within the Wolin National Park. This area is a frontal moraine, characterized by considerable differences in elevation, and bordered by a high cliff on the seaward side. The oldest oak trees are few specimens growing as a remainder within a considerably younger stand. From the remainder of the study area, we selected old stands characterized by good health and growth dynamics. These oaks are growing in both continuous stands, and in isolated mid-field enclaves.Samples were collected from individuals of native oak species (Quercus robur and Q. petraea) using Pressler borers, at 1.3 m above ground, at 24 study plots located in Western Pomerania (a total of 358 trees), between 1997 and 2021. In the laboratory, samples were mounted on boards, dried and sliced using a surgical blade in order to obtain a clear view of the tree-rings. Tree-ring widths (TRW) were measured with an accuracy of 0.01 mm under a stereomicroscope, using the TREE RINGS and LDB_Measure (ver. 1.0) programs. All samples were subsequently dated using standard cross-dating methods. Student’s t-test and Gl coherence coefficient (Gleichläufigkeitswert) were computed for the dendrochronological sequences, and visual similarity of the sequence variability was assessed. Based on this, we selected 72 sequences (from various sites in Western Pomerania), characterized by the highest statistical indices (t>4.5 and Gl>65%), and a high visual similarity. These were used to assemble a regional chronology (QUSP_WP, Quercus spp._Western Pomerania), whose quality was tested using Cofecha, part of the DPL software package.The regional chronology QUSP_WP is based on 72 individual growth curves derived from oak trees growing at 24 sites in Western Pomerania. The assembled chronology spans 458 years, representing the period from 1564 to 2021. The mean tree-ring width equals 1.02 mm/year. The QUSP_WP chronology displays long-term fluctuations. Until about 1750, there is a clear decreasing trend, which is replaced by an increasing trend that lasts until about 1920. After that, another gradual, long-term decrease in tree-ring width is observed. Notably, a clear increase in tree-ring width is also observed in the last 20 years. The observed fluctuations are likely due to the diverse ages of the oak trees, whose tree-ring series were included in the assembled chronology, and from the impact of conditions within the habitats, in which the trees grow.Tree-ring width of regional oak chronology (QUSP_WP, spans 458 years); 1st column - year, 2nd column - tree-ring width in mm.</p
Local chronology of Pinus sylvestris and Pinus xrhaetica form peat bog "Bór na Czerwonem" (Orava-Nowy Targ Basin, S Poland)
No full textThe "Bór na Czerwonem" peat bog is located in the southern part of Poland, in the Małopolska province in the Nowy Targ commune. The nature reserve was established here in 1925. The location of the peat bog can be determined by geographical coordinates: 49º27'31.91" N and 20º02'29.14" E. The peat bog belongs to a domed raised bog. At its highest point it reaches a height of 617.3 m a.s.l., and the surroundings are located lower by about 2.2 m. Its length is about 1000 m and width 500 m. The central part of the reserve is a a domed raised bog with an area of about 36 ha, the entire reserve currently covers about 114.66 ha, and its buffer zone 68.4 haSamples (cores) from trees were taken with Pressler borer at a height of 1.3-1.5 m a.g.l. during the 2024 growing season. Discs were collected from the ground surface in December 2024 from trees previously removed during peatland reclamation – winter 2023/2024. In total, cores were collected from 23 trees and discs from 45 trees. Tree-ring width (TRW) was measured under a stereoscopic microscope down to 0.01 mm, using LBD_Measure software (version 1.0). A total of 140 measuring radius and 7285 tree-rings were measured. Due to the high pith eccentricity, the large number of rings with compression wood, the large number of missing rings and the low statistical and graphical agreement for measurements from discs, it was decided to base the chronology only on samples from cores.The BC chronology representing P. sylvestris and P. xrhaetica (cores) growing in the “Bór na Czerwonem” peat bog was compiled from 16 individual growth curves, and spans 59 years from 1965 to 2023. For the period of 42 years (1982-2023) EPS > 0.85. The sequences included in the chronology are characterized by high graphical and statistical consistency (mean correlation 0.587). The average TRW of the studied trees is 1.2 mm/year, ranging from 0.8 (BC14) to 1.6 mm/year (BC15). Standard deviation (STD) for BC chronology is 0.546 mm, while for the indexed chronology it is 0.332 mm, autocorrelation order 1 (AC1) is 0.613 and 0.539, respectively, and mean sensitivity (MS) is 0.283 and 0.245, respectively. In the course of the chronology, a slight downward trend of TRW is observed in the period 1986-2005, and after 2006 TRW ranges from 0.9 to 1.6 mm/year.File with data of P. sylvestris and P. xrhaetica local chronology (BC chronology): 1st column - year, 2nd column and next - tree-ring width (TRW) of individual trees in mm (tree1, tree2, …), next column - local chronology in mm (bold numbers), last column - number of samples in a given year.</p
Local chronologies of yew (Taxus baccata L.) in Poland
No full textThe eastern boundary of Taxus baccata L. range transects Poland. The analyses were performed on 34 yew populations which are protected as parts of nature reserves, as monuments of nature, or which are planned to be protected (Table 1). Samples were collected with the Pressler borer at breast-height from 25 trees in every area studied (in some cases, due to a low number of trees or constraints imposed by permits, the number of trees sampled was lower). The samples were collected from a total of 774 trees yielding 1307 profiles (Table 1).The tree ring width was measured to 0.01 mm (a total of 99,628 tree rings were measured). The classical dating techniques (i.a., the cross-dating method) were subsequently used to reconstruct 34 local chronologies (Table 2). The longest dendrochronological series (267 years covering the period of 1741-2007) was that obtained from the yew trees growing in the “Cisy w Czarnem” reserve (CZA). Five chronologies were more than 200 years long; 12 were longer than 100 years, the remaining ones representing young trees: the shortest chronology, produced by the yews growing in the “Zdroje” reserve (ZDR) covered as short a period as 38 years (1965-2002) (Table 2). The mean tree ring width was 0.84 mm and ranged from 0.27 mm in the MI population to 1.47 mm in the ZDR yews.Files with data of yew tree-ring width and yew local chronologies (for example: CJ chronology): 1st column - year, 2nd column and next - tree-ring width of individual trees in mm (tree1, tree2, …), next column - local chronology in mm (bold numbers), last column - number of samples in a given year.</p
Local chronology of Intermediate Hawthorn (Crataegus media Bechst.), Poland
No full textLocal chronology of Intermediate Hawthorn (Crataegus media Bechst.), STLocation of the research area: STOBNO - ST (N: 53°25'04.59 "E: 14°24'17.12", 45 m above sea level), NW Poland (about 2.2 km east from the Polish-German border, and about 5 km to the west of Szczecin city limits), on a morainic plateau composed of Last Glacial sediments, in a typically agricultural landscape.At present, it is a monospecific mid-field woodlot, formed by trees and shrubs of intermediate hawthorn (Crataegus media Bechst.), composed of several hundred individuals of this species, of varying age. The woodlot is about 75 m long and 20-25 m wide, located on a SE-facing scarp rising up to 4 m above the surrounding. The substratum is composed of boulder clay, on which a cover of brown soils has developed. From all sides, the woodlot is surrounded by farmland.Samples were taken using Pressler drills, at a level of 1.3 m above ground. A total of 22 trees were sampled, including 30 trunks (numerous hawthorns had 2-3 trunks), yielding 52 wood cores.The chronology, code-named ST, was compiled based on dendrochronological curves derived from 20 trees, including 24 trunks. The ST chronology spans 56 years from 1965 to 2020, however, only for the period 1981-2020 (40 years) the chronology is made up of 10 or more samples.</p
Local chronologies of introduced and native coniferous tree species growing in northwestern Poland (Barlinek Forest Inspectorate)
No full textLocal chronologies of introduced and native coniferous tree species growing in northwestern Poland (Barlinek Forest Inspectorate) Six tree species were selected for the study. Two of these species have natural occurrences in Poland: Scots pine (Pinus sylvestris) - PS and Common larch (Larix decidua) - LD. The remaining four species were introduced from North America: Lawson Cypress (Chamaecyparis lawsoniana) - CL, Western red cedar (Thuja plicata) - TP, Douglas fir (Pseudotsuga menziesii) - PM and Eastern white pine (Pinus strobus) - PST.Field works were carried out in July 2020 (C. lawsoniana, T. plicata), June 2023 (L. decidua, P. menziesii) and November 2023 (P. sylvestris, P. strobus). Tree height was measured using a Nikon Forestry Pro II laser rangefinder. The trunk diameter was measured using a medium gauge at a height of 1.3 m above ground level. Sampling for dendrochronological analyses was performed on the healthiest trees, i.e., those with no apparent trunk damage. Samples were taken from 131 trees using a Pressler borer at a height of 1.3 m above ground level (Table 1). In the laboratory, the samples were glued to boards, dried and cut with a knife to obtain a clear view of the tree-ring boundaries. Tree ring width (TRW) was measured under a stereoscopic microscope to 0.01 mm using LBD_Measure software (version 1.0).Cross-dating between the individual tree TRW time series was performed using on-screen visual comparisons (high visual similarity), and statistical parameters commonly used as cross-dating coefficients in dendrochronology: Student’s t-test, r correlation coefficient and Gleichläufigkeit (GL%). To check the annual variability of the TRW, standard deviation (STD), mean sensitivity (MS) and autocorrelation coefficient lagged by one year (AC) were also calculated (Table 2).The T. plicata and the P. menziesii trees reach the tallest heights (34 m). The L. decidua and the P. strobus display slightly lower heights (31 and 30 m, respectively). The lowest heights were reached by the P. sylvestris (23.5 m) and the C. lawsoniana (22 m) trees. The P. menziesii trees are distinguished by the highest average trunk diameter (66 cm, ranging from 44 to 99 cm). The lowest trunk diameter was observed for the C. lawsoniana: on average 36 cm, ranging from 27 to 51 cm (Table 1).A chronology was compiled for each studied species. The shortest chronology C. lawsoniana (CL) spans 114 years from 1906 to 2019, and the longest chronologies span 136 years (from 1887 to 2022, L. decidua - LD chronology) and 135 years (from 1887 to 2023, P. sylvestris - PS chronology) (Table 2). On average, a chronology is based on 18 individual growth curves, ranging from 13 curves for the P. strobus (PST) chronology to 21 curves for the L. decidua - LD chronology. The average tree-ring width is the lowest for the PS (P. sylvestris) chronology (1.62 mm/year) and for the PST (P. strobus) chronology (1.69 mm/year), while the highest value is recorded for the TP (T. plicata) chronology (2.80 mm/year).The most convergent chronology pair, as expressed by the t index, are PM/TP chronologies (t=11.21). High t values (>7.0) are also obtained for the following pairs of chronologies: CL/PM and PS/PST. The lowest t index values are observed for the CL/PST chronologies (2.30). Low t index values (t<3.0) are also displayed by the pairs CL/LD and LD/PS (Table 3). As expressed by the GL index, the PS and PST chronologies represent the most convergent chronology pair (73%). GL values >65% are also obtained for the following pairs of chronologies: LD/PS, CL/PS, PM/PS, CL/PM and PM/PST. The lowest GL value was obtained for the CL/LD pair (44%). Comparably low GL values (<50%) were noted for the pairs of chronologies: LD/PST, CL/TP and PST/TP (Table 3). Files with data of coniferous tree-ring width and local chronologies (PS, LD, CL, TP, PM, PST): 1st column - year, 2nd column and next - tree-ring width of individual trees in mm (tree1, tree2, …), next column - local chronology in mm (bold numbers), last column - number of samples in a given year.Table 1. List of research plots with basic information.Table 2. Basic statistics of measured and index (residual) local coniferous chronologies: P. sylvestris (PS), L. decidua (LD), C. lawsoniana (CL), T. plicata (TP), P. menziesii (PM) and P. strobus (PST). Abbreviations: TRW – tree-ring width; SD – standard deviation; AC – first order autocorrelation; MS – mean sensitivity; EPS – Expressed Population Signal; rbt – series intercorrelation.Table 3. Similarity of local chronologies of P. sylvestris (PS), L. decidua (LD), C. lawsoniana (CL), T. plicata (TP), P. menziesii (PM) and P. strobus (PST) as measured with t and GL (%) values.</p
Local chronology of Common horse-chestnut (Aesculus hippocastanum L.), BU
No full textLocal chronology of Common horse-chestnut (Aesculus hippocastanum L.), BULocation of the research area: BUK - BU (53.4937872 N, 14.3575283 E, 22 m above sea level), NW Poland (about 0.4 km east from the Polish-German border, and about 10 km to the north-west of Szczecin city limits), on a morainic plateau composed of Last Glacial sediments, in a typically agricultural landscape. Common horse-chestnut trees growing along a 400 m section of a public road in a village of Buk in Dobra Commune in West Pomerania Province. The trees were planted on both sides of the road, forming an avenue. From both sides, the avenue is surrounded by farmland. Samples were taken using Pressler drills, at a level of 1.3 m above ground. The chronology, code-named BU, was compiled based on dendrochronological curves derived from 22 trees. The BU chronology spans 137 years from 1880 to 2016, however, only for the period 1901-2016 (116 years) the chronology is made up of 10 or more samples (EPS>0.85). This indicates that the trees were about 145 years old, and the avenue was planted in the 1880s. Mean TRW (tree-ring width) was 3.54 mm, for individual trees: 2.22-4.31 mm. In 2000 Common horse-chestnut trees were infested by the insect pest horse-chestnut leaf miner (HCLM).</p
Local chronologies of horse chestnut from forest and mid-field habitat, Krzymów (NW Poland)
No full textThe horse chestnut (Aesculus hippocastanum L.) has been cultivated in Poland for nearly 400 years. It is frequently planted in urban spaces, along streets, in parks, within residential districts, as well as along roads in open landscape, and in historic palace gardens. The studied avenue of the horse chestnut trees is located along a local road to Krzymów, a village in NW Poland, Western Pomeranian Voivodeship (52.9824869 N, 14.3481286 E, 45-50 m a.s.l.). The avenue was planted in the 2nd decade of the 20th century. The trees forming the avenue (2.5 km long, east-west trending) are growing in a mid-field habitat (FIELD) and in a forest habitat (FOREST), which enables a comparison among trees growing in these habitats. Dendrometric analyses were performed on 100 trees, and dendrochronological analyses were performed for 32 trees, with equal number of trees sampled in each habitat. The FIELD chronology spans 103 years (1916-2018, EPS>0.85: 1922-2018), the FOREST chronology spans 101 years (1918-2018, EPS>0.85: 1929-2018). The average tree-ring width equals 2.82 mm, ranging from 1.56 to 3.31 mm (Table 1).Files with data of horse chestnut tree-ring width and horse chestnut local chronologies (FIELD and FOREST chronology): 1st column - year, 2nd column and next - tree-ring width of individual trees in mm (tree1, tree2, …), next column - local chronology in mm (bold numbers), last column - number of samples in a given year.</p
Local chronologies of one-seeded and intermediate hawthorn (Crataegus monogyna, C. xmedia) in Poland
No full textTwo hawthorn species occur in Poland: the one-seeded hawthorn (Crataegus monogyna) and the Midland hawthorn (C. laevigata). There is also a natural hybrid of these two, the intermediate hawthorn (C. xmedia Bechst.). All these species occur in the study area. The analyses were performed on 9 hawthorn populations (Table 1). Two populations are natural hybrids, intermediate hawthorn (C. xmedia, ST and LB), the remaining seven plots are populations of the one-seeded hawthorn (C. monogyna). Two populations (LB and ST) are located in northern Poland, four populations (MA, CI, ZB and DB) are located within the lowlands of central Poland, and three populations are located within mountain areas: WA in the Sudetes, and WG and LE in the Carpathians. The ST study plot is located at the lowest elevation (45 m a.s.l.), and the LE plot is located at the highest elevation (540 m a.s.l.) (Table 1). Samples were taken using a Pressler borer from a total of 192 trees (359 samples). Tree-ring width was measured down to 0.01 mm. The average tree ring width in the studied hawthorn populations ranged from 1.42 to 3.25 mm/year (Table 2). Using well-established cross-dating methods, nine local chronologies were compiled, spanning from 45 to 72 years. EPS values >0.85 are noted from 1972 to 2020/2021 (Table 2).Files with data of hawthorn tree-ring width and hawthorn local chronologies (for example: LB chronology): 1st column - year, 2nd column and next - tree-ring width of individual trees in mm (tree1, tree2, …), next column - local chronology in mm (bold numbers), last column - number of samples in a given year.</p
Local chronologies of Sawara cypress [Chamaecyparis pisifera (Siebold & Zucc.) Endl.] in Poland
No full textLocal chronologies of Sawara cypressFive stands of Sawara cypress [Chamaecyparis pisifera (Siebold & Zucc.) Endl.], from northwestern and central Poland were selected for study:1. Arboretum Glinna (GL), ϕ 53°17'N, λ 14°43'E, 68 m a.s.l., 12 sampled trees;2. Drawsko Pomorskie (DR), ϕ 53°52'N, λ 15°82'E, 115 m a.s.l., 21 sampled trees;3. Sieraków (SI), ϕ 52°65'N, λ 16°09'E, 48 m a.s.l., 23 sampled trees;4. Arboretum Wirty (WI), ϕ 53°89'N, λ 18°37'E, 131 m a.s.l., 21 sampled trees;5. Arboretum Rogów (RO), ϕ 51°49'N, λ 19°53'E, 194 m a.s.l.), 20 sampled trees.Samples were taken from 97 trees (dendrochronological analysis was based on a total of 167 cores, which yielded over 11300 measured tree-rings), using Pressler borers at breast-height. Tree-ring widths were measured down to 0.01 mm. Tree-ring width in the studied populations of Sawara cypress varies (from 1.94 to 4.47 mm). The oldest Sawara cypresses grow in Glinna Arboretum and are nearly 130 years old. The youngest ones grow in Rogów Arboretum (67 years old) and Wirty Arboretum (58 years old).The longest chronology was obtained for the GL plot. It spans 122 years (1899-2020), for EPS>0.85: 75 years (1946-2020), and the shortest chronology – spanning only 58 years – was compiled for the WI plot (1961-2018), for EPS>0.85: 50 years (1969-2018). Chronology DR spans 1116 years (1905-2020), for EPS>0.85: 89 years (1932-2020), chronology SI spanning 82 years (1939-2020), for EPS>0.85: 75 years (1946-2020) and chronology RO spans 67 years (1953-2019), for EPS>0.85: 58 years (1962-2019).</p
- …
