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1

Developing millennial tree-ring chronology for Turku (Åbo) and comparing palaeoclimatic signals inferred from archaeological, subfossil and living Pinus sylvestris data in Southwest Finland

Helama Samuli, Ratilainen Tanja, Ruohonen Juha, Taavitsainen Jussi-Pekka

Studia Quaternaria

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2024

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Vol. 41, Nr 1

1--11

EN

Archaeological and living tree data were used to construct tree-ring chronologies over the medieval (AD 1183–1430) and recent (AD 1812–2020) periods in Turku, which is historically an important population centre in Southwest Finland and the country. Comparisons between the two tree-ring assemblages, and between the previously built chronologies from the Åland (historical timber) and Tavastia (lacustrine subfossils and living trees) sites, provided ways of understanding the growth patterns and their linkages to climatic, environmental, and edaphic factors. Tree growth in and around Turku was affected by warm-season precipitation and winter temperature. Similar relationships were previously evident also in the Åland tree rings, whereas the data from a wetter Tavastia site did not exhibit similar precipitation signal. The site conditions influence also the correlations which are higher between Turku and Åland than between Turku and Tavastia chronologies. Construction of long continuous chronology is impaired by human-related activities, the Great Fire of Turku in 1827 and logging, which have diminished the availability of dead and living-tree materials, respectively. These conditions lead to hardships of filling the gap between the medieval and recent periods and updating the archaeological datasets with compatible living-tree data, which are both demonstrated by our results.

2

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.

3

Kościół św. Leonarda w Lipnicy Murowanej – analiza substancji zabytkowej. Wybrane zagadnienia

Budziakowski Mateusz, Piotrowska Natalia, Kłusek Marzena

Wiadomości Konserwatorskie

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2020

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Nr 62

136--147

PL

Artykuł dotyczy problematyki historii, konstrukcji, wyposażenia oraz datowania zabytkowego kościoła św. Leonarda w Lipnicy Murowanej. Kościół ten jest jedną z drewnianych świątyń Małopolski znajdujących się na Liście Światowego Dziedzictwa UNESCO. Stopień i sam fakt zachowania obiektu, jego architektura i wyposażenie wyraźnie wskazują na międzynarodową rangę obiektu. Liczne polichromie, tryptyki oraz ornamentyka stropów podkreślają jego estetykę, dzięki czemu stanowi on jeden z ciekawszych zabytków w tym regionie. W artykule przedstawiono także wyniki badań przeprowadzonych metodą dendrochronologiczną, które pozwoliły na zweryfikowanie hipotezy dotyczącej pochodzenia i datowania jednego z elementów konstrukcyjnych w świątyni (tzw. słupa Światowida).

EN

This paper discusses the subject matter of the history, structure, furnishing and dating of the historic Church of St. Leonard in Lipnica Murowana. This church is one of the wooden temples of Lesser Poland that are inscribed on the UNESCO World Heritage Sites List. The degree and indeed the very fact of the building’s preservation, its architecture and furnishings clearly indicate its international rank. Numerous polychromes, triptychs and the ornamentation of its ceilings highlight its aesthetic, making it one of the more interesting historical sites in this region. The paper also presents the results of dendrochronological studies which allowed the authors to verify a hypothesis concerning the origin and dating of one of the church’s structural elements (the so-called „Column of Światowid”).

4

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.

5

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.

6

Interpretation of soil erosion in a Polish loess area using OSL, 137Cs, 210Pbex, dendrochronology and micromorphology – case study: Biedrzykowice site (s Poland)

Poręba Grzegorz, Śnieszko Zbigniew, Moska Piotr, Mroczek Przemysław, Malik Ireneusz

Geochronometria

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2019

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Vol. 46, no. 1

57--78

EN

Loess areas used for agriculture are susceptible to soil erosion. The intensive process of soil erosion in Polish loess areas began with the onset of the Neolithic and has continued intermittently until today. This work presents the results of soil erosion from simultaneous use of the 137Cs and 210Pbex methods on an agricultural field located on loess slope. Moreover, to establish the age of accumulated sediment connected with water slope erosion, OSL dating, selected physicochemical and micromorphological analyses were applied. The reference values of the 137Cs and 210Pbex fallout for the studied site (Biedrzykowice, the Proszowice Plateau, Małopolska Upland) equal 2627 (45% connected with Chernobyl) and 4835 Bq·m–2, respectively. The results of the 137Cs and 210Pbex inventories measured for the agricultural field range from 730 to 7911 and from 1615 to 11136 Bq·m–2, respectively. The mean soil erosion is about 2.1 kg·m–2·a–1 (about 1.4 mm·a–1). The accumulation of the colluvial sediments started in the Neolithic and drastically increased in the Middle Ages. The examined gully catchment in Biedrzykowice has probably developed quite rapidly as a result of increased erosion. This resulted in the abandonment of this area as farmland and, consequently, in the minimization of water erosion on the slope due to the entrance of woody vegetation in this area. Erosion processes were highly intensified during the last 70 years as a result of deforestation after World War II and intensive agricultural reuse of this area after a break, as indicated by isotope measurements and dendrochronology.

7

Can we distinguish between tree-ring eccentricity developed as a result of landsliding and prevailing winds? consequences for dendrochronological dating

Wistuba M., Malik I., Krąpiec M.

Geochronometria

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2018

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Vol. 45, no. 1

223--234

EN

The aim of our study was to compare patterns of tree-ring eccentricity developed in Norway spruce trees as a result of landsliding with the one caused by the prevailing wind (in 2 study sites), and with the normal growth of trees (in 2 reference sites). We sampled 20 trees per study site and 10 per reference site. Two cores were taken from each tree (120 cores in total) from the upslope and downslope, windward and leeward sides of stems. Ring widths measured on opposite sides of stems were compared using the method of percent eccentricity index. Graphs of the index obtained for individual trees were analysed. Statistical indicators were calculated for a percent eccentricity index. Disturbance events were dated and the response index was calculated. The results show that the patterns of eccentricity developed as a result of the prevailing winds and due to landsliding differ from one another and from the reference sites. The results suggest that the impact of the prevailing wind on tree growth is more severe than the impact of landsliding. The difference may result from the slow-moving character of the landslide under study. The results, however, indicate that wind impact should be taken into account in dendrogeomorphic research and that the impact of mass movements should be considered in dendroecological studies on wind.

8

Dendrochronology and extreme pointer years in the tree-ring record (AD 1951–2011) of polar willow from southwestern Spitsbergen (Svalbard, Norway)

Owczarek P., Opała M.

Geochronometria

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2016

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Vol. 43, no. 1

84--95

EN

Greater warmth and precipitation over the past several decades in the High Arctic, as recorded in meteorological data, have caused shrub expansion and affected growth ring widths. The main aim of the study was to develop a tree-ring chronology of polar willow (Salix polaris Wahlenb.) from southwest Spitsbergen, attempt to explain its extreme pointer years (extremely low value of growth-ring widths) and to demonstrate the dendrochronological potential of this species. This plant is a deciduous, prostrate, creeping dwarf shrub that produces anatomically distinct annual growth rings with the consistent ring width variation. After using serial sectioning we developed rigorously cross-dated ring width chronology covering the period 1951–2011. Since the beginning of the 1980s an increase of the mean and maximum growth ring width has been observed which is consistent with the increase of both temperature and precipitation in the Arctic reported from meteorological sources. Nine negative extreme years were distinguished and explained by complex hydroclimatic drivers, which highlight the importance of availability of moisture from snowpack and spring precipitation. An additional negative factor present in the years with very low dwarf shrubs growth is rapid thawing and fast freezing during winter as well as low sunshine duration. Our results contradict the prior assumption that inter-annual tree growth variability of dwarf shrubs from polar regions is controlled simply by temperature.

9

Activity of Slow-Moving Landslides Recorded in Eccentric Tree Rings of Norway Spruce Trees (Picea Abies Karst.) — An Example from the Kamienne MTS. (Sudetes MTS., Central Europe)

Malik I., Wistuba M., Migoń P., Fajer M.

Geochronometria

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2016

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Vol. 43, no. 1

24--37

EN

We found ubiquitous evidence of ongoing slope instability by analysing the variability of tree-ring eccentricity index in trees growing on three apparently relict landslide slopes in the Sudetes (Poland, Central Europe). Slow movement of these landslide bodies occurs in the present-day conditions and is recorded almost every year, although with variable intensity. Correlation of dendrochronological record with the rainfall record from a nearby station in Mieroszów for the 1977–2007 period is very poor for two deep-seated rotational slides at Mt Suchawa and Mt Turzyna but considerably better for a shallow flowslide at Mt Garbatka. While this may reflect higher permeability of heavily jointed rocks involved in deep-seated sliding this could be linked with imperfections in the rainfall record. Dendrochronology proved capable of detecting minor displacements within landslides which otherwise show no geomorphic evidence of recent activity. Therefore, claims for the entirely relict nature of the landslides are not substantiated.

10

Automation of annual tree increment measurement using vision system

Sioma A., Socha J.

Drewno : prace naukowe, doniesienia, komunikaty

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2016

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vol. 59, nr 196

19--30

EN

The objective of the study was the development of an automatic measurement method for tree ring increments using a vision system combined with an XYZ scanner. The elaborated method allows for the measurement of increments on cross-section a tree discs or on increment bores. The solution utilizes the XYZ scanner equipped with a vision system, enabling increment measurement during sample scanning. The vision system collects and analyses images of a wood sample. The splicing of partial images enables the construction of a full image of rings, visible on the entire sample surface. Image construction of the studied sample based on a set of magnified partial pictures enables the attainment of very high resolutions, which in top end optical systems, greatly surpasses the resolutions obtained using traditional scanners. The system works automatically and the algorithm of the increment measurement is based on the image analysis of the sample area and is realized in the acquisition time of partial pictures by the vision system. Configuration of the measurement system enables selection of the field of view and measuring resolution. The maximum obtained in the presented system is 0.001 mm.

11

Zastosowanie metod dendrochronologicznych w badaniach lawin śnieżnych

Kaczka R. J., Janecka K, Lempa M., Rączkowska Z.

Landform Analysis

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2015

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Vol. 28

15--27

PL

Lawiny śnieżne pomimo swojej siły pozostawiają niejednorodny zapis w środowisku. Z tego powodu rekonstrukcja momentu wystąpienia i wielkości lawiny jest zadaniem trudnym. Jednym z pośrednich dowodów ich aktywności są miejsca, gdzie lawiny docierają do lasu pozostawiając swój ślad w skali makro (obniżanie górnej granicy lasu) i mikro (uszkodzenia pojedynczych drzew). Odpowiednio zaadaptowane metody dendrochronologiczne pozwalają datować zdarzenia lawinowe. W wyniku połączenia analiz dendrochronologicznych z innymi metodami badawczymi uzyskujemy wielowymiarowy obraz aktywności lawin w przeszłości. Zastosowanie podstawowych technik dendrochronologicznych do datowania zdarzeń lawinowych zostało omówione na przykładzie wyników badań w Białym Żlebie w Tatrach Wysokich. Opracowana dla tego miejsca rekonstrukcja aktywności lawin obejmuje ponad 100 lat i wskazuje na pięć dużych zdarzeń lawinowych w okresie od 1912 do 2009 roku. Włączenie do analiz technik GIS umożliwiło rozszerzenie rekonstrukcji o elementy przestrzenne, informujące o zasięgu przeszłych zdarzeń.

EN

Despite their strength, snow avalanches leave a very diverse record in the environment. For this reason, the reconstruction of the occurrence, time and magnitude of avalanches is a really demanding task. It can only be performed in places where avalanches reach forests, leaving their marks in the macroscale (lowering the upper timberline) and microscale (damaging individual trees). Appropriately adapted dendrochronological methods allow dating the avalanche events. Combining the dendrochronological analyses with other techniques enables to obtain a multi-dimensional image of avalanche events. The application of the basic dendrogeomorphological techniques is discussed on the example of the results of the research from the Biały Żleb chute located in the High Tatras. The obtained reconstruction of avalanche activity covers more than 100 years and points to five major avalanche events in the period from 1912 to 2009. The employment of GIS techniques allowed to extend the reconstruction by a spatial element indicating the range of the past events.

12

Czynniki uaktywniające i zróżnicowanie czasowe przemieszczeń koluwiów w różnych częściach stoku osuwiskowego : analiza dendrochronologiczna na przykładzie osuwiska Skalka (Moravskoslezské Beskydy)

Łuszczyńska K., Wistuba M.

Landform Analysis

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2015

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Vol. 28

103--113

PL

Celem badań było określenie zmienności czasowej osuwania i stwierdzenie różnic w aktywności poszczególnych części stoku osuwiskowego. Zastosowano metody dendrochronologiczne: dla 60 świerków pospolitych analizowano dekoncentryczność przyrostów rocznych. Największą dynamikę osuwania stwierdzono w latach: 1975, 1993, 1985, 1968–1969, 1995. Liczba zaburzeń wzrostu radialnego drewna świadczących o osuwaniu w poszczególnych latach dobrze odpowiada przebiegowi sum opadów półrocza letniego (np. osuwanie i opady w latach: 1968, 1972, 1975, 1977, 1985, 2010) oraz w mniejszym stopniu zimowego. Wyniki wskazują na nierównoczesną aktywność poszczególnych części osuwiska i uruchamianie różnych jego partii podczas różnych epizodów opadowych oraz prawdopodobnie w efekcie innych czynników uaktywniających (np. trzęsień ziemi z lat 1992–1993 o epicentrach w Beskidzie Sądeckim).

EN

The aim of the study was to determine the temporal variability o landsliding and differences in the activity of individual part of a small landslide. Dendrochronological methods have been applied: tree-ring eccentricity was analysed for 60 Norway spruce trees. The most dynamic landsliding occurred in: 1975, 1993, 1985, 1968–1969 and 1995. The number of wood-growth disturbances recording landsliding in particular years matches well with precipitation totals for summer half-years (e.g. landsliding and precipitation in: 1968, 1972, 1975, 1977, 1985, 2010) and to the smaller degree with totals for winter half-years (e.g. 1961). Results indicate uneven activity of particular landslide sections. The movement in particular parts of the landslide is triggered during various precipitation events or due to other factors (e.g. 1992–1993 earthquakes with epicentres in Beskid Sądecki Mts).

13

Historical water-powered ferrous metallurgy reconstructed from tree-rings and lacustrine deposits (Mała Panew Basin, southern Poland)

Malik I., Wistuba M., Opała M., Franek M., Woskowicz-Ślęzak B., Mańczyk G., Tyrol Cz.

Geochronometria

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2015

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Vol. 42, no.1

79--90

EN

According to historical sources in the basin of Mała Panew River there were at least 56 water- powered iron smelters from 14th–19th century. Now only two metallurgy plants work in the area. Many of the former smelting settlements ceased to exist. Historical data on the smelting industry in the area are often scarce. The aim of the study was to reconstruct the history of ferrous metallurgy from (1) the remains of wooden historical buildings, (2) remains of charcoal kilns and (3) deposits from former smelter pond. Results show that Regolowiec smelting settlement existed already in the 17th century (at least several decades earlier than historical written sources suggest) and was later repaired after destruction caused probably by floods. Charcoal used for iron smelting in the ironworks in Brusiek on the Mała Panew River was burnt at the turn of the 18th century. This is in accordance with historical sources indicating particular prosperity of the metallurgy in that period. Upstream of the ironworks in Brusiek in the first half of the 17th century a large pond existed flooding the floor of the Mała Panew valley. Study has shown that the pond was at least 100 years older than historical sources have indicated.

14

An 854-year tree-ring chronology of scots pine for south-west Finland

Helama S., Holopainen J., Timonen M, Mielikainen K

Studia Quaternaria

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2014

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Vol. 31, Nr 1

61--68

EN

A near-millennial tree-ring chronology (AD 1147-2000) is presented for south-west Finland and analyzed using dendroclimatic methods. This is a composite chronology comprising samples both from standing pine trees (Pinus sylvestris L.) and subfossil trunks as recovered from the lake sediments, with a total sample size of 189 tree-ring sample series. The series were dendrochronologically cross-dated to exact calendar years to portray variability in tree-ring widths on inter-annual and longer scales. Although the studied chronology correlates statistically significantly with other long tree-ring width chronologies from Finland over their common period (AD 1520-1993), the south-west chronology did not exhibit similarly strong mid-summer temperature or spring/early-summer precipitation signals in comparison to published chronologies. On the other hand, the south-west chronology showed highest correlations to the North Atlantic Oscillation indices in winter/spring months, this association following a dendroclimatic feature common to pine chronologies over the region and adjacent areas. Paleoclimatic comparison showed that tree-rings had varied similarly to central European spring temperatures. It is postulated that the collected and dated tree-ring material could be studied for wood surface reflectance (blue channel light intensity) and stable isotopes, which both have recently shown to correlate notably well with summer temperatures.

15

Formy osuwiskowe w Górach Kamiennych (Sudety Środkowe) : kryteria identyfikacji i oceny zagrożeń

Migoń P., Kacprzak A., Malik I., Kasprzak M.

Landform Analysis

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2014

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Vol. 26

39--60

PL

W Górach Kamiennych (Sudety Środkowe) powszechnie występują formy rzeźby związane z osuwiskami, które powstały w okresie przedhistorycznym. Zostały one rozpoznane na podstawie terenowego kartowania geomorfologicznego, wspomaganego interpretacją cyfrowego modelu wysokości zbudowanego z wysokorozdzielczych danych LiDAR, i dokumentują różne rodzaje przemieszczeń: translacyjne, rotacyjne, spływanie materiału, rozciąganie, a lokalnie również obrywy. Badania stopnia rozwoju gleb wskazują, że obok osuwisk starych, stabilnych w holocenie występują formy młode, które powstały lub były reaktywowane w holocenie. Na holoceńską aktywność wskazują także nieliczne daty radiowęglowe. Deformacje przyrostów rocznych drzew porastających osuwiska stwierdzone w trakcie badań dendrochronologicznych pozwalają wnioskować o utrzymującej się niestabilności niektórych form i powolnym ruchu. Ogólnie zagrożenia związane z osuwiskami w Górach Kamiennych w obecnych warunkach środowiskowych i przy obecnym stanie zagospodarowania można uznać za niewielkie, nieznana jest jednak możliwa reakcja osuwisk na postępujące zmiany klimatu i ewentualne zmiany użytkowania ziemi. Artykuł ma głównie charakter przeglądowy i zawiera podsumowanie wcześniej prowadzonych badań i ich opublikowanych rezultatów.

EN

In the Kamienne Mountains (Middle Sudetes) landforms resulting from prehistoric landslides are common. They have been recognized through detailed field geomorphological mapping, aided by interpretation of high-resolution digital elevation models built from LiDAR data, and provide evidence of different types of movement, including translational and rotational slides, flowslides, lateral spreading, and rock fall. Soil research focused on soil development shows that ancient, stable landslide terrains coexist with much younger landslides, initiated or reactivated in the Holocene. Holocene activity is also suggested by sparse radiocarbon dates. Tree ring deformations revealed by dendrochronological research allow to infer persistent instability of certain landslides and their ongoing slow movement. Generally, hazards associated with landslides in the Kamienne Mts, given the current environmental conditions and land use, may be considered as low, but a possible reaction of landslide systems to climate change and any major land use changes is unknown. The paper is largely of review type and summarizes results obtained and published before.

16

Wieliczka Salt Mine and its history written in annual growth rings of spruce wood

Szychowska-Krąpiec E., Dudek K.

Geological Quarterly

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2014

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Vol. 58, No. 3

617--622

EN

This paper presents results of dendrochronological analysis of spruce wood from the Wieliczka Salt Mine, one of the oldest mines in Poland. The wood came from the first level of the mine, from casings of drifts, chambers, mineshafts, short shafts, galleries and chapels. The oldest wood, representing spruce trees cut down in the 15th century, appears in the Wałczyn, August and Dusząca chambers, Bąkle chamber and Powroźnik gallery, as well as the cast between the Kaczorowski and Sroki chambers. Younger wood, from the 16th and 17th century, was recognized in the Krupiński, Dusząca, Reyna and Weszki chambers, the Leszno and Karol galleries, the Sułów short shaft, and the Lizak chapel. The 18th–19th century wood appears in the August, Wałczyn, Dusząca, Rex and Kloski chambers, the Klemens gallery, the Piżmowa chapel, and the Wałczyn short shaft. In two excavations of the August and Weszki chambers, fragments of 20 th century wood were recognized. Wood from old mines is a valuable source of information on history of the mining excavations or tools used in the mines. It also allows extending the scope of research of the mining archaeology.

17

Tree ring analysis as an indicator of environmental changes caused by tourist trampling — A potential method for the assessment of the impact of tourists

Ciapała S., Adamski P., Zielonka T.

Geochronometria

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2014

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Vol. 41, no. 4

392--399

EN

This paper shows that tree-ring trends might be used for the assessment of the intensity of trampling along touristic tracks in the forests. The study aims at determining the effects of trampling, on the dynamics of annual increments in trees subject to pressure from hiking tourism. The studies were conducted at a spruce stand in the Tatra Mts., on sections of different trails. Within each trail, four transects were determined. Transects include the zones with damage from trampling and the un-affected areas, treated as a reference zones. Selected trees growing in both zones were sampled by coring and the core samples were used to develop sequences of annual increment widths. Next, the dynamics of increments in trees growing in the tourist zone and the reference zone were compared. The decrease in the annual increments was significantly more rapid in trees growing directly along the trail that those in trees deep in the forest stand in one locality. This finding may testify the adverse effects of hiking along tourist routes on the radial increments in trees in the neighbourhood of the trails. The results of the study indicate that the impact of trampling in the form of soil compaction and mechanical damage to root systems of trees may, to some extent, be compensated by better light access and lessened competition experienced by trees growing along the edges of hiking trails. Tree-ring analyses might be an efficient alternative for assessment of tourism intensity conducted by the other methods.

18

Sub-fossil wood from the Rucianka raised bog (NE Poland) as an indicator of climatic changes in the first millennium BC

Barniak J., Krąpiec M., Jurys L.

Geochronometria

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2014

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Vol. 41, no. 1

104--110

EN

The dendrochronological studies were carried out on very well preserved sub-fossil pine wood found in the biogenic deposits of the Rucianka raised bog (NE Poland). Local floating chronol-ogies, covering the period 990-460 cal BC, were dated on the basis of radiocarbon analyses. Growth depressions in annual tree-ring widths indicated periodical deterioration of the environmental condi-tions, which affected tree growth. Identified germination and dying-off phases (GDO) should be re-lated to the wetter climatic periods. The extinction of trees took place during periods of higher groundwater level which, in turn, caused favourable conditions for growth of young pines.

19

Radiocarbon and dendrochronological dating of Sub-fossil oaks from Smarhoń riverine sediments

Vitas A., Mažeika J., Petrošius R., Pukienė R.

Geochronometria

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2014

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Vol. 41, no. 2

121-128

EN

Sub-fossil oaks from Smarhoń in Belarus have been investigated and tree-ring chronologies were assembled. According to radiocarbon dating, the oldest oak grew from 5782–5612 cal BC and the youngest from 1575–1747 cal AD. Radiocarbon and dendrochronological dating of 97 samples, four single series, 10 mean curves (containing 2–9 series) and three chronologies (10–25 series) were constructed. The longest chronology (No. 16), covering 549 years, was absolutely dated against various oak chronologies of Polish/Baltic origin to AD 778–1326. Germination and dying-off phases were assessed from the three best replicated chronologies.

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A lake fortress, a floating chronology, and an atmospheric anomaly: the surprising results of a radiocarbon wiggle-match from Āraiši, Latvia

Meadows J., Zunde M.

Geochronometria

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2014

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Vol. 41, no. 3

223--233

EN

An Iron Age timber settlement which, in view of the defensive structures uncovered, is described as a lake fortress, on an island in Lake Āraiši, north-eastern Latvia, was excavated in 1965–69 and 1975–79 by teams led by Jānis Apals, who distinguished five construction phases. Dendrochronological analysis produced a c. 100-year floating chronology for Norway spruce (Picea abies (L.) Karst.) timbers from the earliest phase. A 14C wiggle-match was undertaken to obtain an absolute date range for the final year of the floating chronology, and thus for the construction of the settlement. Ten blocks of wood from one timber, each comprising 6-11 years and collectively spanning the whole 93-year tree-ring series, were dated by AMS. Using the IntCal13 calibration data, there is a 95% probability that the felling date of this timber falls in the range 775–784 cal AD. It appears, however, that the AD 775 spike in the atmospheric 14C level occurred within the 6-year span of the last sample. On this basis, we can narrow the date of construction to 776–780 cal AD. This date is significantly earlier than those reported in previous publications.