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Dendrochronological record of soil creep and landslide activity – the comparison of tree-ring eccentricity and compression wood (examples from the Kamienne Mts., Poland)

Sitko Katarzyna, Wistuba Małgorzata, Malik Ireneusz, Krąpiec Marek, Yu Ruide, Zhang Haiyan

Geology, Geophysics and Environment

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2022

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Vol. 48, no. 2

133--146

EN

Forested mountain slopes can be simultaneously affected by soil creep and landslide activity, both of which cause the tilting of tree stems, with the result that their dendrochronological record of tree-ring eccentricity and compression wood is potentially similar. There is a need to identify similarities and differences in these records and thus our research aimed to compare patterns of eccentricity and compression wood developed by trees under the impact of soil creep and landslides. We sampled trees growing on a landslide and creeping slopes in the Kamienne Mts., with 21 Norway spruce trees were sampled on each site. We found several main differences between the dendrochronological record of landslide activity and soil creep. On the landslide we found larger number of dendrochronological events, stronger and more variable eccentricity and a similar number of upslope and downslope events. On creeping slopes, upslope eccentricity events predominate, and the number of eccentricity events dated in all trees increases in time. We also compared the utility of eccentricity and compression wood for dating mass movements. They differ in their sensitivity to stem tilting. Thus, in analyses of landslide activity and soil creep activity, it is recommended to include both wood anatomy features.

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Status of the AMS graphitization system in the dendrochronological laboratory at AGH-UST, Kraków

Wiktorowski Damian, Krąpiec Marek, Rakowski Andrzej, Cherkinsky Alexander

Geochronometria

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2020

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Vol. 47, no.1

112--117

EN

A new system for the preparation of graphite samples for radiocarbon (14C) measurement using an accelerator mass spectrometer (AMS) has been built in the Dendrochronological Laboratory at AGH-UST, Kraków. This system consists of three independent components. The first is the equipment for mechanical and chemical sample pre-treatment. The second is the vacuum line for sample sealing and the purification of CO2. The third and central part of this system is a graphitization line, where graphite is produced from CO2. In the first stage, chemical sample preparation was carried out to remove impurities. IAEA and NIST OxII standard materials were converted to CO2 without pre-treatment. In the next step, samples were combusted to CO2. The resulting CO2 was released under vacuum and cryogenically purified for subsequent graphitization. The performance of the system was tested with NIST OxII, IAEA standards (IAEA C5, C6 and C7) and background samples. The test confirms good reproducibility of results obtained for the samples prepared using this system. The results of the 49 samples of NIST Ox-II, IAEA standards and blank samples were presented in this article.

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Dendrochronological dating of St. George’s Orthodox Church in Drohobych, Ukraine

Krąpiec Marek, Szychowska-Krąpiec Elżbieta, Tymoshenko Leonid, Myska Roman

Geochronometria

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2020

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Vol. 47, no.1

93--100

EN

St. George’s Orthodox Church in Drohobych is a wooden monument of sacral architecture, recently registered in the UNESCO World Heritage List. However, clear, unequivocal written sources about the origins of the structure are lacking. Absolute dating was attempted with the dendrochronological method, and it was carried out in a noninvasive way due to the status and value of the object. Construction elements of the church were documented with over 40 macrophotographs. The studies were made for selected elements, displaying distinct perpendicular or tangential cross sections. Most of the elements examined represented fir wood. It turned out that the wood used for the construction of this church was contemporaneous and most likely represented a single construction phase. The 124-year chronology based on correlated curves covers the period 1464–1598 AD. Construction elements with the outermost rings retained indicate that the timber was harvested in the 1590s. In most cases, the outermost rings were lacking, which allowed only for dating terminus post quem. The youngest preserved rings (1598 AD) from the church wood apparently reveal the dates of both the wood harvesting and the structure’s construction. Such a dating may indicate that the church mentioned in the sources as purchased in Nadiyevo in 1657 AD could be the basis for the rebuilding of Drohobych St. George’s Orthodox Church, only adapted to the new conditions. The church later underwent renovation, consisting in reconstruction of the dome in 1821 AD.

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A Tree-Ring chronology from Allerød–YD transition from Koźmin (Central Poland)

Krąpiec Marek, Szychowska-Krąpiec Elżbieta, Barniak Joanna, Goslar Tomasz, Kittel Piotr, Michczyńska Danuta J., Michczyński Adam, Piotrowska Natalia, Rakowski Andrzej, Wiktorowski Damian

Geochronometria

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2020

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Vol. 47, no.1

101--111

EN

Subfossil trunks of pine (Pinus sylvestris L.) from the Late Weichselian were discovered in the site Koźmin in the Koło Basin, central Poland (Dzieduszyńska et al., 2014a). Another part of organic sediments with trunks was excavated in the frame of the research project. Altogether 224 samples from Koźmin were analysed dendrochronologically; they represented generally young trees, 40 to 70 years old. Based on the most convergent sequences, the chronology 2KOL_A1 was produced, 210 years in length. With the wiggle-matching method, it was dated to ca. 13065–12855 cal BP. Dendrochronological dating of trunks buried in organic sediments, most of which occurred in situ, revealed that tree deaths occurred successively, over more than 100 years. That could have been due to unfavourable climatic conditions, as well as extreme events, e.g. strong winds.

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Dendrogeomorphological analysis of the Sawicki Landslide in the Beskid Niski Mountains (S Poland)

Krąpiec Marek, Nawrocka Natalia, Margielewski Włodzimierz, Szychowska-Krąpiec Elżbieta

Geological Quarterly

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2019

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Vol. 63, No. 4

801--810

EN

We applied dendrochronological analysis to study an extensive (~2.5 km long) complex-type landslide in the Beskid Niski Mountains (Polish Flysch Carpathians), which was rejuvenated in historical time (the earliest transformation occurred in 1913). We used three complementary methods (dating of eccentricity of annual growth rings, eccentricity indices, and analysis of reaction wood), based on seven species of deciduous and coniferous trees. A total of 204 trees were sampled and 408 cores collected using a Pressler increment borer. Based on the dendrochronological analysis, the activity of various parts of the landslide in the past century is presented, which appears to have been diverse and influenced mostly by precipitation. The upper part of the landslide was active from the 1920s until the 1940s. In the middle section of the landslide, intensifications of gravitational movement were repeatedly recorded after intense rainfalls throughout the entirety of the last century. The highest landslide activity was dendrochronologically detected in the 1980s and 1990s. Increasing landslide activity during so-called “dry years” may have been related to quick drying of the bedrock, resulting in changes in rock strength parameters. Our results indicate significant susceptibility of this particular slope-valley geosystem in response to even slight hydrogeological changes (including dryness), which can trigger ground movement.

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Assessment of landslide hazard from tree-ring eccentricity and from compression wood : a comparison

Łuszczyńska Katarzyna, Malik Ireneusz, Wistuba Małgorzata, Krąpiec Marek

Geological Quarterly

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2019

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Vol. 63, No. 2

296--301

EN

We have compared maps of landslide activity and hazard, developed with the use of two different dendrochronological indicators: tree-ring eccentricity and reaction (compression) wood. The maps were prepared based on 125 Norway spruce (Picea abies L. Karst.) trees growing at 44 sampling points, distributed over an area of 3.75 km2. In general, the two maps show similar patterns of landslide activity. However, tree-ring eccentricity yielded a greater number of dated events (246) compared to compression wood (129). Besides the differences in the absolute values of dating results, the general landslide activity and hazard zonation based on both disturbances are similar. Both growth disturbances develop as a result of stem tilting. Eccentricity develops after slight tilting, while compression wood is developed when tilting is more significant. Because of the differences in the strength of disturbing factors, which cause the development of compression wood and growth eccentricity, the best approach would be to combine the results of dating obtained from the two methods. The dendrochronological analysis of tree growth disturbances (eccentric growth and compression wood) is a promising approach for determining landslide hazards in forested mountain areas and can be applied in spatial management.