Journal articles: 'Dendrochronology Tree-rings'

1

Benarie, Michel. "Tree rings — Basics and application of dendrochronology." Science of The Total Environment 84 (August 1989): 299–300. http://dx.doi.org/10.1016/0048-9697(89)90392-6.

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Cruz, Pedro, John Wihbey, Avni Ghael, Felipe Shibuya, and Stephen Costa. "Dendrochronology of U.S. immigration." Information Design Journal 25, no. 1 (December 31, 2019): 6–20. http://dx.doi.org/10.1075/idj.25.1.01cru.

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Abstract Immigrants are central to the identity of the United States, the population of which has grown in number and diversity as a function of new arrivals from around the globe. This article describes a visualization project that uses the visual metaphor of tree rings to explore the contribution of immigrants to the country’s population. Immigrants and native-born persons are represented and differentiated as cells in trees, with layered annual rings capturing patterns of population growth. These rings register, in their shape and color, certain environmental conditions. In order to mimic the natural process by which growth rings are formed, we devised a computational system that simulates the growth of trees as if cells were data-units. Dendrochronology involves dating certain events by analyzing patterns of growth in trees. Analogously, in our visualizations the rings can be counted and dated, showing the chronological evolution of the population. The dendrochronology theme is a poetic take on the data, yet it is also a functional and conceptual space that is used to construct language and rationales on that data. The tree-growth process not only inspires the appearance of the visualizations but also informs the rules of the computational system that creates them.

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Biondi, Franco. "From Dendrochronology to Allometry." Forests 11, no. 2 (January 27, 2020): 146. http://dx.doi.org/10.3390/f11020146.

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The contribution of tree-ring analysis to other fields of scientific inquiry with overlapping interests, such as forestry and plant population biology, is often hampered by the different parameters and methods that are used for measuring growth. Here I present relatively simple graphical, numerical, and mathematical considerations aimed at bridging these fields, highlighting the value of crossdating. Lack of temporal control prevents accurate identification of factors that drive wood formation, thus crossdating becomes crucial for any type of tree growth study at inter-annual and longer time scales. In particular, exactly dated tree rings, and their measurements, are crucial contributors to the testing and betterment of allometric relationships.

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Turkon, Paula, Sturt W. Manning, Carol Griggs, Marco Antonio Santos Ramírez, Ben A. Nelson, Carlos Torreblanca Padilla, and Eva Maria Wild. "APPLICATIONS OF DENDROCHRONOLOGY IN NORTHWESTERN MEXICO." Latin American Antiquity 29, no. 1 (December 14, 2017): 102–21. http://dx.doi.org/10.1017/laq.2017.60.

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Although dendrochronological methods have the potential to provide precise calendar dates, they are virtually absent in Mesoamerican archaeological research. This absence is due to several long-standing, but erroneous, assumptions: that tree rings in this region do not reflect annual growth and environmental variability, that an adequate number of samples do not exist, and that tree-ring measurements cannot be useful without modern trees to link prehispanic chronologies. In this article we present data from the sites of La Quemada and Los Pilarillos, located in the Malpaso Valley, Zacatecas, to demonstrate that suitable archaeologically derived samples of dendrochronologically useful species do exist, that the samples from these sites are measurable and cross-datable, and that the tree rings can yield precise calendar dates using a method that “wiggle-matches” radiocarbon dates on tree-ring sequences. The work demonstrates the potential of these methods to address chronological, and, in the future, climatic questions, which have so far eluded archaeological work in the region.

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Martin, R. R., T. Sylvester, and M. C. Biesinger. "Secondary ion mass spectroscopy (SIMS) in the analysis of elemental micropatterns in tree rings." Canadian Journal of Forest Research 24, no. 11 (November 1, 1994): 2312–13. http://dx.doi.org/10.1139/x94-298.

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Secondary ion mass spectroscopy (SIMS) has been used to examine elemental micropatterns in tree rings. Elevated potassium was detected in discrete rings, suggesting that this technique may have a wide application in dendrochronology.

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Divya, K., and Sukhvir Kaur. "A Study on Tree Rings: Dendrochronology using Image Processing." IOP Conference Series: Materials Science and Engineering 1022 (January 19, 2021): 012115. http://dx.doi.org/10.1088/1757-899x/1022/1/012115.

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Boreux, J. J., P. Naveau, O. Guin, L. Perreault, and J. Bernier. "Extracting a common high frequency signal from northern Quebec black spruce tree-rings with a Bayesian hierarchical model." Climate of the Past Discussions 5, no. 2 (March 4, 2009): 797–816. http://dx.doi.org/10.5194/cpd-5-797-2009.

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Abstract. Dendrochronology, the scientific dating method based on the analysis of tree-ring growth patterns, has been frequently applied in climatology. The basic premise of dendroclimatology is that tree rings can be viewed as climate proxies, i.e. rings are assumed to contain some hidden information about past climate. From a statistical perspective, this extraction problem can be understood as the search of a hidden variable which represents the common signal within a collection of tree-ring width series. Classical average-based techniques used in dendrochronology have been, with different degrees of success (depending on tree species, regional factors and statistical methods), applied to estimate the mean behavior of this latent variable. Still, a precise quantification of uncertainties associated to the hidden variable distribution is difficult to assess. To model the error propagation throughout the extraction procedure, we propose and study a Bayesian hierarchical model that focuses on extracting an inter-annual high frequency signal. Our method is applied to black spruce (Picea mariana) tree-rings recorded in northern Quebec and compared to a classical average-based techniques used by dendrochronologists.

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Creasman, Pearce Paul. "Tree Rings and the Chronology of Ancient Egypt." Radiocarbon 56, no. 4 (2014): S85—S92. http://dx.doi.org/10.2458/azu_rc.56.18324.

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A fundamental aspect of ancient Egyptian history remains unresolved: chronology. Egyptologists (and researchers in related fields that synchronize their studies with Egypt) currently rely on a variety of insufficiently precise methodologies (king lists, radiocarbon dating, etc.) from which to derive seemingly “absolute” dates. The need for genuine precision has been recognized for a century, as has the potential solution: dendrochronology. This manuscript presents a case for further progress toward the construction of a tree-ring chronology for ancient Egypt.

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Bayliss, Alex, and Ian Tyers. "Interpreting Radiocarbon Dates Using Evidence from Tree Rings." Radiocarbon 46, no. 2 (2004): 957–64. http://dx.doi.org/10.1017/s0033822200036018.

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Often it is not possible to date a sample of wood from the final growth ring of the tree from which it came. In these cases, an “old-wood offset” is apparent. A number of quantitative approaches for the assessment of this offset are available, dependent on the actual tree rings that have been dated. A range of examples are given, demonstrating how such radiocarbon measurements can be interpreted using additional information from archaeology and dendrochronology.

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Creasman, Pearce Paul. "Tree Rings and the Chronology of Ancient Egypt." Radiocarbon 56, no. 04 (2014): S85—S92. http://dx.doi.org/10.1017/s0033822200050396.

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A fundamental aspect of ancient Egyptian history remains unresolved: chronology. Egyptologists (and researchers in related fields that synchronize their studies with Egypt) currently rely on a variety of insufficiently precise methodologies (king lists, radiocarbon dating, etc.) from which to derive seemingly “absolute” dates. The need for genuine precision has been recognized for a century, as has the potential solution: dendrochronology. This manuscript presents a case for further progress toward the construction of a tree-ring chronology for ancient Egypt.

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Severin Šikanja and Nevena Milovanović. "New dendroclimatological research in oak, S (Quercus Frainetto Ten.) forestry in Šumadija-Region- (Central Serbia) as a basis for climate change monitoring." World Journal of Advanced Research and Reviews 11, no. 2 (August 30, 2021): 249–59. http://dx.doi.org/10.30574/wjarr.2021.11.2.0292.

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In this work present study to describe the survey of climatic change in the case in Šumadija-Central Serbia. Climate change due to a fragile ecosystem in semi-arid, and arid region such as Serbia is one of the most challenging climatological and hydrological problems. Dendrochronology, wich uses tree rings to their exact year of formation to analyse temporal and spatial patterns of processes in the physical and cultural sciences, can be used to evaluate the effects of climate change. In this study, the effects of climate change werw simulated using dendrochronology (tree rings) and an artificial neural network (ANN) for the period from 1900—2015. The present study was executed using the (Quercus frainetto Ten.). Tree rings width, temperature and precipitation were the input parameters for the study, and climate change parameters were the outputs. After the training process, the model was verified. The verified network and tree rings were used to simulate climatic parameter changes during the past times. The results showed that the integration of dendroclimatology and an ANN renders a high degree of accuracy and efficiency in the simulation of climatic change. The results showed that the climatic of the study area changed from semiarid, to arid, and its annual precipitation decreased significantly.

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Latimer, Shane D., Margaret S. Devall, Charles Thomas, Erik G. Ellgaard, Satish D. Kumar, and Leonard B. Thien. "Dendrochronology and Heavy Metal Deposition in Tree Rings of Baldcypress." Journal of Environmental Quality 25, no. 6 (November 1996): 1411–19. http://dx.doi.org/10.2134/jeq1996.00472425002500060035x.

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Biondi, Franco, and Julianna E. Fessenden. "Radiocarbon Analysis of Pinus Lagunae Tree Rings: Implications for Tropical Dendrochronology." Radiocarbon 41, no. 3 (1999): 241–49. http://dx.doi.org/10.1017/s0033822200057118.

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A promising species for tropical dendrochronology is Pinus lagunae, a pine tree found in Baja California Sur (Mexico) around lat 23.5°N. In 1995, we sampled a total of 27 wood cores from 13 Pinus lagunae trees in Sierra La Victoria (23°36'N, 109°56'W), just north of Sierra La Laguna, at an elevation of 1500–1600 m. Selected trees were locally dominant, but their ring-width patterns could not be crossdated. To test the hypothesis that visible growth layers in Pinus lagunae are formed annually, we measured radiocarbon amounts in individual rings by means of accelerator mass spectrometry (AMS). Twenty-three 14C measurements were used to trace the location of the 1963–64 “bomb spike” in 3 wood increment cores. By comparing the location of that δ14C extreme with the number of visible radial wood increments, it was possible to conclude that 2 cores had a number of locally absent rings, while the 3rd one included a few years with more than one growth layer. Therefore, ring-width patterns of sampled Pinus lagunae were not consistent from one tree to another, most likely because of climatic regime in combination with microsite features. While the possibility of generating Pinus lagunae tree-ring chronologies cannot entirely be ruled out, the development of dendrochronological proxy records of climate from coniferous species in tropical North America should focus on species and sites that experience a more pronounced seasonality.

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Baillie, M. G. L. "Volcanoes, ice-cores and tree-rings: one story or two?" Antiquity 84, no. 323 (March 1, 2010): 202–15. http://dx.doi.org/10.1017/s0003598x00099877.

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Good archaeology relies on ever more precise dates – obtainable, notably, from ice-cores and dendrochronology. These each provide year-by-year sequences, but they must be anchored at some point to real historical time, by a documented volcanic eruption, for example. But what if the dating methods don't agree? Here the author throws down the gauntlet to the ice-core researchers – their assigned dates are several years too old, probably due to the spurious addition of ‘uncertain’ layers. Leave these out and the two methods correlate exactly…

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Mohammad Reza, Khaleghi. "Application of dendroclimatology in evaluation of climatic changes." Journal of Forest Science 64, No. 3 (March 28, 2018): 139–47. http://dx.doi.org/10.17221/79/2017-jfs.

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The present study tends to describe the survey of climatic changes in the case of the Bojnourd region of North Khorasan, Iran. Climate change due to a fragile ecosystem in semi-arid and arid regions such as Iran is one of the most challenging climatological and hydrological problems. Dendrochronology, which uses tree rings to their exact year of formation to analyse temporal and spatial patterns of processes in the physical and cultural sciences, can be used to evaluate the effects of climate change. In this study, the effects of climate change were simulated using dendrochronology (tree rings) and an artificial neural network (ANN) for the period from 1800 to 2015. The present study was executed using the Quercus castaneifolia C.A. Meyer. Tree-ring width, temperature, and precipitation were the input parameters for the study, and climate change parameters were the outputs. After the training process, the model was verified. The verified network and tree rings were used to simulate climatic parameter changes during the past times. The results showed that the integration of dendroclimatology and an ANN renders a high degree of accuracy and efficiency in the simulation of climate change. The results showed that in the last two centuries, the climate of the study area changed from semiarid to arid, and its annual precipitation decreased significantly.

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Balzano, Angela, Klemen Novak, Miha Humar, and Katarina Čufar. "Application of confocal laser scanning microscopy in dendrochronology." Les/Wood 68, no. 2 (December 30, 2019): 5–17. http://dx.doi.org/10.26614/les-wood.2019.v68n02a01.

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We used the Confocal Laser Scanning Microscope (CLSM) Olympus LEXT OLS5000 for non-destructive observation and image analysis of wood anatomy traits in growth layers of tree species from different climatic zones. In European beech (Fagus sylvatica), where tree rings can generally be recognised, we discuss the changes in tree-ring structure due to adverse effects (insect attacks). Growth layers in Mediterranean Aleppo pine (Pinus halepensis) from south-eastern Spain are not always annual and contain numerous intra-annual density fluctuations (IADFs). Ocote pine (Pinus oocarpa) growing at high elevation in Honduras showed growth layers with clear growth ring boundaries and IADFs. In both pines, CLSM allowed us to recognise and measure tracheid parameters to define density fluctuations. In tropical true mahogany (Swietenia macrophylla) from Venezuela and cedrela (Cedrela odorata) from Costa Rica, we studied the growth layers with variable dimensions of vessels demarcated by marginal axial parenchyma.

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Solomina, Olga, and Paolo Cherubini. "“Tree rings and people”, an international conference on the future of dendrochronology." Dendrochronologia 20, no. 1-2 (January 2002): 13–19. http://dx.doi.org/10.1078/1125-7865-00004.

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Stahle, David W. "Useful Strategies for the Development of Tropical Tree-Ring Chronologies." IAWA Journal 20, no. 3 (1999): 249–53. http://dx.doi.org/10.1163/22941932-90000688.

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This paper outlines efficient strategies for the development of long, climatically sensitive tree-ring chronologies in the tropics. Effective strategies include sampling useful temperate or subtropical species that extend naturally into the tropics; sampling species in botanical families that have already provided examples useful for dendrochronology (e. g., Pinaceae, Taxodiaceae, Verbenaceae); targeting deciduous species in seasonally dry forests; and sampling species described in the literature or found in xylaria that have promising anatomical features such as ring porosity and marginal parenchyma. Dendrochronology can also be used to test the annual nature of growth banding in tropical species. The cross-dating oflong ring-width time series between individual trees and between multiple sites in a region is strong evidence that the growth rings are indeed synchronized with the annual calendar. This can be confirmed if the ring-width data are also strongly correlated with long annual or seasonalized records of climate variability. Blind cross-dating tests to identify the cutting dates of known-age timbers can provide a final proof that a species produces reliable annual growth rings.

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Hua, Quan, Mike Barbetti, Ugo Zoppi, David M. Chapman, and Bruce Thomson. "Bomb Radiocarbon in Tree Rings from Northern New South Wales, Australia: Implications for Dendrochronology, Atmospheric Transport, and Air-Sea Exchange of CO2." Radiocarbon 45, no. 3 (2003): 431–47. http://dx.doi.org/10.1017/s0033822200032793.

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We have analyzed by radiocarbon 27 consecutive single rings, starting from AD 1952, of a preliminarily cross-dated section (DFR 021) of Pinus radiata, which grew in Armidale, northern New South Wales, Australia. The bomb 14C results suggested the possibility of 2 false rings, and, consequently, 2 misidentified rings in the preliminary count for this section. This possibility was supported by a better ring-width correlation between the revised DFR 021 count and other Pinus radiata chronologies in the study region. This indicated that bomb 14C is a useful tool to complement the standard techniques of dendrochronology in tree species where annual rings are not always clearly defined.

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Boreux, J. J., P. Naveau, O. Guin, L. Perreault, and J. Bernier. "Extracting a common high frequency signal from Northern Quebec black spruce tree-rings with a Bayesian hierarchical model." Climate of the Past 5, no. 4 (October 14, 2009): 607–13. http://dx.doi.org/10.5194/cp-5-607-2009.

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Abstract. One basic premise of dendroclimatology is that tree rings can be viewed as climate proxies, i.e. rings are assumed to contain some hidden information about past climate. From a statistical perspective, this extraction problem can be understood as the search of a hidden variable which represents the common signal within a collection of tree-ring width series. Classical average-based techniques used in dendrochronology have been applied to estimate the mean behavior of this latent variable. Still, depending on tree species, regional factors and statistical methods, a precise quantification of uncertainties associated to the hidden variable distribution is difficult to assess. To model the error propagation throughout the extraction procedure, we propose and study a Bayesian hierarchical model that focuses on extracting an inter-annual high frequency signal. Our method is applied to black spruce (Picea mariana) tree-rings recorded in Northern Quebec and compared to a classical average-based techniques used by dendrochronologists (Cook and Kairiukstis, 1992).

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Becker, Bernd. "An 11,000-Year German Oak and Pine Dendrochronology for Radiocarbon Calibration." Radiocarbon 35, no. 1 (1993): 201–13. http://dx.doi.org/10.1017/s0033822200013898.

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Sequences of dendrodated tree rings provide ideal sources for radiocarbon calibration. The wood structure of trees consists of continuous series of annual growth layers, the carbon content of which can be 14C-dated and calibrated to calendar yr. The cellulose and lignin of trees deposited in river gravels or peat-bog sediments below the water table are often very well preserved, even after several millennia. Such tree-trunk deposits are well protected from contamination by younger or older organic materials. Further, the physical and chemical structure of wood allows a strong chemical pretreatment of samples for 14C analysis.

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Campelo, F., C. Nabais, I. García-González, P. Cherubini, E. Gutiérrez, and H. Freitas. "Dendrochronology of Quercus ilex L. and its potential use for climate reconstruction in the Mediterranean region." Canadian Journal of Forest Research 39, no. 12 (December 2009): 2486–93. http://dx.doi.org/10.1139/x09-163.

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Holm oak ( Quercus ilex L.) is a long-lived species widely distributed across the Mediterranean Basin, with potential value for dendrochronology and dendroclimatology. However, tree-ring dating in Q. ilex is a complex task that has limited the number of dendrochronological studies using this evergreen species. In the present work, it was investigated if old Q. ilex trees showed annual tree rings and whether they can be used as climate proxies. A long tree-ring chronology (126 years) of Q. ilex was developed using cross sections of 20 trees from the Guadiana river basin (Portugal). The high correlation among tree-ring series suggested that tree growth was controlled mainly by climate. Response function analysis showed a positive correlation between tree-ring width and precipitation from October(t–1) of the previous year to January(t) of the current year and in May(t). Tree-ring width was negatively correlated with the North Atlantic oscillation that exerts a strong influence on the precipitation over Iberia. Negative pointer years were triggered by dry years and became more frequent during the last decade of the 20th century. In conclusion, it is possible to accurately date old Q. ilex trees, and their tree rings could be used for climate reconstructions across the Mediterranean.

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Lussier, Jean-Martin, Roger Gagné, and Gilles Bélanger. "Improving visual detection of growth rings of diffuse-porous hardwoods using fluorescence." Forestry Chronicle 80, no. 5 (September 1, 2004): 612–16. http://dx.doi.org/10.5558/tfc80612-5.

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This paper presents a method for preparing wood sections and reading tree rings in diffuse-porous hardwoods that is more efficient than the standard sanding method. The planning of fresh samples and the use of an ultraviolet light source in conjunction with a fluorescent dye reduced the preparation time by 39%. No significant differences were found between the two methods for the time needed for ring count. The fluorescent method can be used for both wood sections and cores, and it can be applied to coniferous species. Key words: dendrochronology, tree ring analysis, diffuse-porous hardwoods, fluorescence, Acer, Betula

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Sakamoto, Minoru, Masataka Hakozaki, Nanae Nakao, and Takeshi Nakatsuka. "Fine Structure and Reproducibility of Radiocarbon Ages of Middle to Early Modern Japanese Tree Rings." Radiocarbon 59, no. 6 (December 2017): 1907–17. http://dx.doi.org/10.1017/rdc.2017.133.

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ABSTRACTThis study carried out accelerator mass spectrometry radiocarbon (AMS 14C) measurement of Japanese tree rings dating from the middle to early modern eras to investigate calibration curve fine structure. Tree-ring ages were determined by dendrochronology or δ18O chronology for Japanese trees. 14C ages from the 15th century to the middle of the 17th century followed the IntCal13 calibration curve within measurement error. Different patterns of fluctuations during the latter half of the 17th century to the early the 18th century were observed in different tree samples. In the 19th century, patterns of 14C ages of different samples appeared similar but did not exactly match each other.

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Bonde, Niels, and Arne Emil Christensen. "Dendrochronological dating of the Viking Age ship burials at Oseberg, Gokstad and Tune, Norway." Antiquity 67, no. 256 (September 1993): 575–83. http://dx.doi.org/10.1017/s0003598x00045774.

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Dendrochronology now provides a date, exact nearly to the year, for three Viking Age burial mounds of special importance for chronology in Scandinavia and across early medieval northern Europe. Their dating used to depend on the style of the carved wooden artefacts in the grave goods; now the grave-goods are exactly and independently dated by the tree-rings, those same links will provide dating bridges across the Viking world.

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Kaiser, Klaus Felix. "Two Creeks Interstade Dated through Dendrochronology and AMS." Quaternary Research 42, no. 3 (November 1994): 288–98. http://dx.doi.org/10.1006/qres.1994.1079.

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AbstractDendrochronological analysis of fossil wood from Two Creeks, Wisconsin, reveals that the Two Creekan Intetstade lasted at least 252 yr. The sites crossdated by tree rings cover an area of about 970 km2. AMS determinations from the beginning and end of the chronology open a 14 C time window for the episode from 12,050 to 11,750 yr B.P. The interval is contemporaneous with the Older Dryas in northern Europe. The development of a forest covering at least 970 km2 on the western shore of Lake Michigan indicates a water level about as low as in modern times. Glacier retreat must have opened drainage channels either through the Straits of Mackinac or via the Indian River Plateau into the eastern lakes. The beginning of the tree-ring chronology coincides with the peak of meltwater pulse 1A at 12,000 yr B.P. Increased amounts of meltwater seem to have disturbed the heat exchange between the waters and the atmosphere in the North Atlantic off the Gulf of St. Lawrence or affected the δ18O-ratio of the evaporation, causing the climatic or isotopic reversal of the Older Dryas in Greenland and northern Europe.

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Quarta, Gianluca, Alfredo Di Filippo, Lucio Calcagnile, Marisa D’Elia, Franco Biondi, Emanuele Presutti Saba, Michele Baliva, Giuseppe De Vivo, Aldo Schettino, and Gianluca Piovesan. "Identifying the 993–994 CE Miyake Event in the Oldest Dated Living Tree in Europe." Radiocarbon 61, no. 5 (May 14, 2019): 1317–25. http://dx.doi.org/10.1017/rdc.2019.37.

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ABSTRACTCombined dendrochronology and accelerator mass spectrometry radiocarbon (AMS 14C) dating analyses were used in order to date an old living tree named Italus, growing in the Pollino massif in Southern Italy. Wiggle match AMS 14C dating analysis was performed on a 320-yr-long floating chronology obtained by cross-dating four wood cores extracted from the exposed roots of the tree. Following this approach, an age for the tree of ≈1230 yr was estimated. This age makes Italus the oldest living tree in Europe. High-resolution 14C dating analyses performed on single rings extracted from the tree stem allowed us to identify the 993–994 CE large excursion in atmospheric 14C concentration (Miyake event) revealing for the first time its presence in the Mediterranean basin.

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Hammerschlag, Izabela, Kita D. Macario, Ana Carolina Barbosa, Gabriel de Assis Pereira, Camila Laís Farrapo, and Francisco Cruz. "Annually Verified Growth of Cedrela Fissilis from Central Brazil." Radiocarbon 61, no. 4 (June 6, 2019): 927–37. http://dx.doi.org/10.1017/rdc.2019.52.

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ABSTRACTGiven the difficulty in obtaining robust chronologies from tree rings in tropical regions, the search for appropriate species is very important. Both dendrochronology and radiocarbon (14C) measurements are required to validate the use of any specific tree. Some species have proved to be reliable for representing atmospheric 14C concentration over time, such as Cedrela fissilis and Araucaria angustifolia. However, not only the species have to be validated, but also different climatic conditions may result in different growth patterns for the same species. In this work, we study the annual growth rings of Cedrela fissilis from a dry tropical forest patch typical of a highly seasonal climate in central Brazil. 14C accelerator mass spectrometry (AMS) was used to compare the isotopic ratios of tree rings with the 14C concentrations in the atmosphere during the nuclear tests based on curve Bomb13SH 1-2. Results are similar to the bomb peak curve within the period from 1958 to 1980 AD and serve as a crucial test for the cross-dating analyses using the skeleton plot technique.

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Mareš, V., and J. Blahovec. "Variation of the tree ring micro-hardness demonstrated on spruce wood." Journal of Forest Science 50, No. 3 (January 11, 2012): 135–41. http://dx.doi.org/10.17221/4608-jfs.

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Micro-hardness was used for the study of wood structure (Norway spruce) in the line perpendicular to tree rings (radial surface). The steel indentor 0.25 mm in diameter with flat head was used for this purpose. The individual penetration tests were performed at constant velocity 0.0167 mm/sinto a depth of 0.3 mm. Local wood strength was defined as the mean pressure on the indentor head at 0.02 mm penetration. The set of tests (~ 320) gave information about stress variation in dependence on the location of the test place in the tested surface. The stress was understood as a parameter describing the growth properties of wood similarly like the density usually used in dendrochronology. The measured strength variation is in agreement with visually observed tree rings. The acquired data made it possible to determine the mean characteristic points of the tree ring as well as the development of the parameters in dependence on the weather variations.

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Xavier, Carolina Nogueira, Daniela Granato-Souza, Ana Carolina M. C. Barbosa, and José Reinaldo Moreira da Silva. "Tropical dendrochronology applied to invasive tree species in the Brazilian Atlantic Forest." Journal of Forestry Research 32, no. 1 (December 13, 2019): 91–101. http://dx.doi.org/10.1007/s11676-019-01075-9.

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AbstractThe Atlantic Forest is one of the largest and most biodiverse rainforests of South America but anthropogenic activities are drastically changing these landscapes. The invasion of alien or exotic species is one of the greatest threats to biodiversity. There are few studies of invasive species in tropical Brazilian ecosystems. This research examines growth and ecological aspects of Syzygium cumini and Clitoria fairchildiana, two invasive tree species in the Pedra Branca State Park, an Atlantic Forest remnant in southeastern Brazil. Both species were successfully dated, indicating an average age of 58 and 31 years, respectively. A positive relationship between growth and precipitation of the previous growing season suggests an ecological adaptive strategy, which could be facilitating their invasion into the environment. Cumulative growth diameter curves indicate slow and fast growth rates for S. cumini and C. fairchildiana, respectively. Growth release episodes detected in the tree rings indicate increased anthropogenic disturbances over the last 50 years.

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Sass-Klaassen, U., I. Poole, T. Wils, G. Helle, G. H. Schleser, and P. F. van Bergen. "Carbon and Oxygen Isotope Dendrochronology in Sub-Fossil Bog Oak Tree Rings - A Preliminary Study." IAWA Journal 26, no. 1 (2005): 121–36. http://dx.doi.org/10.1163/22941932-90001607.

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Isotope dendroclimatology is a relatively new field investigating environmental factors that control the radial growth of trees. Tree-ring series of sub-fossil bog oaks can be dated from sites across northwest Europe indicating that the environmental change(s) were regional rather than local. Bog oaks show characteristic periods of suppressed growth thought to have resulted from changes in the hydrological status of bogs towards either wetter or drier conditions. This study investigates relative changes in stable carbon (δ13C) and oxygen (δ18O) isotope content in phases of suppressed and normal growth in three bog oaks dated as c. 200 BC to 150 AD from Zwolle, eastem Netherlands. Bog oaks show no clear relationship between tree-ring width and isotopic composition although one tree exhibited relatively depleted values of l3C and 18O with suppressed growth. Suppressed ring growth is characterised by the formation of earlywood only, possibly as a result ofhydrologic alterations that limited the formation of latewood, which would otherwise have locked up a detectable signal in stable isotopic shift.

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Conedera, Marco, Patrick Fonti, Patrik Krebs, and Andreas Rigling. "Jahrringe und Landschaftsentwicklung auf der Alpensüdseite | Tree-rings and landscape development on the southern side of the Alps." Schweizerische Zeitschrift fur Forstwesen 155, no. 6 (June 1, 2004): 191–97. http://dx.doi.org/10.3188/szf.2004.0191.

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Tree-ring analysis is one of the most suitable methods for studying processes in landscape dynamics. In southern Switzerland these dynamics are extremely varied and rapid, which makes the use of dendrochronological and dendroecological methods particularly interesting. In 2003 the Sottostazione Sud delle Alpi of the WSL decided to enlarge its field of activities, making dendrochronology one of their core method of research. First studies are underway and possible applications are presented as case studies in this contribution.

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Sava, Gabriela O., Ionel Popa, Tiberiu B. Sava, Aurelia Meghea, Cristian Mănăilescu, Maria Ilie, Andrei Robu, and Boglárka Tóth. "Intervalidation of Dendrochronology and 14C Dating on a 700-yr Tree-Ring Sequence Originating from the Eastern Carpathians." Radiocarbon 61, no. 5 (May 27, 2019): 1337–43. http://dx.doi.org/10.1017/rdc.2019.56.

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ABSTRACTWe present a comparative study on a 700-yr sequence of dendrochronologically ordered tree-rings of Pinus cembra originating from Eastern Carpathians for the period AD 1009–1709. This period covers the solar minima of the Little Ice Age. The aim of this study was to assess the accuracy of our radiocarbon (14C) determinations interpreted on the IntCal13 calibration data and to observe any apparent offsets. The 14C measurements on single and double tree-rings were “wiggle-matched” to secure the dendrochronology cross-matching of all the Pinus cembra wood pieces. The results showed a very good agreement between the age datasets for four out of five wood trunks. However, for one of them a new cross-matching was performed after a quality assurance test, establishing an earlier 48-yr position, recommended by wiggle-matching Bayesian statistics and dendrochronological analysis. Following this adjustment, the quantification of the 14C level variability with respect to the IntCal13 calibration curve was obtained by calculating Δ14C for all tree-ring samples. As a final conclusion, an insignificant 14C concentration offset of –0.63 ± 3.76‰ was found for the Romanian samples.

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da Costa, Warlen Silva, Maura Da Cunha, Tahysa Mota Macedo, Mariana de Andrade Iguatemy, Alexandre Quinet, Pablo José Francisco Pena Rodrigues, and Claudia Franca Barros. "Cambium phenology and dendrochronology of the endangered tropical tree Ocotea catharinensis Mez." IAWA Journal 42, no. 2 (April 28, 2021): 111–20. http://dx.doi.org/10.1163/22941932-bja10023.

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Abstract Ocotea catharinensis occurs mainly in the Brazilian Atlantic Forest and is highly threatened by timber logging, forest fragmentation, and habitat loss. The remnant populations of this species are genetically rich, which may be related to the presence of long-lived trees, and so it is imperative to understand their growth and age. In this study, we analyzed trees of O. catharinensis from dense ombrophylous forest, its dendrochronological potential, the period of cambial activity and dormancy, and the influence of climate on annual growth. The species showed distinct annually-formed tree-rings, with cambial activity during summer and autumn, and cambial dormancy during winter and spring. A tree-ring width chronology was built from 1852–2015. The estimated age of the sampled trees varied from 40 to 164 years. O. catharinensis in our study site does not show a strong age–diameter relationship, hence similar diameters at breast height resulted in differences in ages by as much as 50 years. The resulting tree-ring width chronology is positively correlated with March precipitation, the transition month between rainy and dry seasons. This study brings valuable contributions to the understanding of the growth of O. catharinensis, which is a novelty for this species and important to the maintenance of these long-lived trees in natural forests.

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ROMO-KRÖGER, C. M., M. J. AVILA, L. C. EATON, and L. A. LÓPEZ. "ANALYSIS OF CONTAMINATING ELEMENTS IN TREE RINGS IN SANTIAGO, CHILE." International Journal of PIXE 06, no. 01n02 (January 1996): 331–37. http://dx.doi.org/10.1142/s012908359600034x.

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Using the 22” isochronous cyclotron at the University of Chile, we have performed PIXE analyses on a group of samples collected from trees of metropolitan parks in Santiago. Dendrochronology was performed on each sample, which was then sectioned for the PIXE and other analyses, neutron activation and electro-chemistry. Available samples are trunk sections or cores obtained by the use of a 4.0 mm stainless steel incremental corer. We took three cores from each tree with permission of the municipalities. For the PIXE we use infinitely thick targets, as wood slabs taken along the trunk radius, and thin targets obtained by acid digestion of wood pieces and deposition on Kapton foils. Self supporting thick targets were placed directly in the PIXE chamber in a position so as to allow the irradiation of a specific annual ring. Potassium and Calcium appear as the most abundant elements in wood Other elements such as S, Cu, Zn, As, Br and Pb were detected in amounts above the natural background in wood, and can be attributed to environmental contamination. The K/Ca ratios appear to be different for each species of tree, and seem to be related to the physico-chemical properties of wood. Preliminary results show important amounts of As and Cu (supposedly from mining origin) with increasing presence in the recent years. Pb and Zn (supposedly from vehicle origin) are also higher in recent years.

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Bayliss, A., P. Marshall, C. Tyers, C. Bronk Ramsey, G. Cook, S. P. H. T. Freeman, and S. Griffiths. "Informing Conservation: Towards 14C Wiggle-Matching of Short Tree-Ring Sequences from Medieval Buildings in England." Radiocarbon 59, no. 3 (August 30, 2016): 985–1007. http://dx.doi.org/10.1017/rdc.2016.61.

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AbstractThis study tested whether accurate dating by accelerator mass spectrometry (AMS) radiocarbon wiggle-matching of short tree-ring series (~30 annual rings) in the Medieval period could be achieved. Scientific dating plays a central role in the conservation of historic buildings in England. Precise dating helps assess the significance of particular buildings or elements of their fabric, thus allowing us to make informed decisions about their repair and protection. Consequently, considerable weight, both financial and legal, can be attached to the precision and accuracy of this dating. Dendrochronology is the method of choice, but in a proportion of cases this is unable to provide calendar dates. Hence, we would like to be able to use 14C wiggle-matching to provide a comparable level of precision and reliability, particularly on shorter tree-ring sequences (~30 annual growth rings) that up until now would not routinely be sampled. We present the results of AMS wiggle-matching five oak tree-ring sequences, spanning the period covered by the vast majority of surviving Medieval buildings in England (about AD 1180–1540) when currently we have only decadal and bidecadal calibration data.

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Eddy, John A. "Book Review: Pioneer of Dendrochronology: Tree Rings and Telescopes: The Scientific Career of A. E. Douglass." Journal for the History of Astronomy 17, no. 1 (February 1986): 69–71. http://dx.doi.org/10.1177/002182868601700112.

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Struble, William T., Joshua J. Roering, Bryan A. Black, William J. Burns, Nancy Calhoun, and Logan Wetherell. "Dendrochronological dating of landslides in western Oregon: Searching for signals of the Cascadia A.D. 1700 earthquake." GSA Bulletin 132, no. 7-8 (January 7, 2020): 1775–91. http://dx.doi.org/10.1130/b35269.1.

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Abstract Large-magnitude earthquakes and hydrologic events in mountainous settings commonly trigger thousands of landslides, and slope failures typically constitute a significant proportion of the damage associated with these events. Large, dormant deep-seated landslides are ubiquitous in the Oregon Coast Range, western United States, yet a method for calculating landslide ages with the precision required to diagnose a specific triggering event, including the A.D. 1700 Cascadia earthquake, has remained elusive. Establishing a compelling connection between prehistoric slope instability and specific triggers requires landslide ages with precision greater than that provided by 14C dating of detrital materials. Tree-ring analysis is the only known method capable of determining landslide age with this precision. Dozens of landslide-dammed lakes in western Oregon present an opportunity to use tree rings from drowned snags, or “ghost forests,” to establish the year of death, and thus landsliding. We cross-dated tree-ring indices from drowned Douglas fir trees with live tree-ring records from the Oregon Coast Range that exhibit synchronous, time-specific patterns due to regional climate variations. Our analyses determined that the landslides responsible for creating Wasson and Klickitat Lakes occurred in A.D. 1819 and 1751, respectively. The 14C dates from selected tree rings and landslide deposit detritus are consistent with our tree-ring analysis, although the ages exhibit high variability, revealing the limitations of using 14C dating alone. Because dendrochronology provides annual precision for landsliding, sampling of tree rings at additional landslide-dammed lakes throughout the Oregon Coast Range can be used to constrain the potential effects of ground motion and major storms on Cascadia landscapes.

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Linares, R., H. C. Santos, A. F. N. Brandes, C. F. Barros, C. S. Lisi, F. C. Balieiro, and S. M. de Faria. "Exploring the 14C Bomb Peak with Tree Rings of Tropical Species from the Amazon Forest." Radiocarbon 59, no. 2 (April 2017): 303–13. http://dx.doi.org/10.1017/rdc.2017.10.

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AbstractIn this work we explore the radiocarbon (14C) signal as an independent tool to assess the year of formation of individual tree rings of tropical species in northern Brazil. Three different species were analyzed in this work: Dipteryx magnifica, Enterolobium maximum, and Hymenolobium petraeum. The studied samples are from the stem of only one individual of each species, all cut down in 2008 in Porto Trombetas, Pará, Brazil. Individual tree rings were identified based on wood anatomy and they were counted from bark to pith. Several rings were selected for 14C analysis in order to cover the overall shape of the 14C atmospheric bomb peak (after 1955). The 14C content was measured at Laboratory of Radiocarbon, Universidade Federal Fluminense (LAC-UFF). Results are compared with the Southern Hemisphere 14C atmospheric calibration curves. For E. maximum and H. petraeum the 14C signal exhibits an overall good match with the SH zone 3 and suggests annual seasonality in the growth-ring formation. These species offer suitable characteristics for dendrochronology. The D. magnifica shows mismatches in the 14C measurements that are likely a result of difficulties in identifying ring boundaries with certainty. Additional techniques may be helpful to disentangle the origin of this discrepancy.

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Dang, Q. L., and V. J. Lieffers. "Climate and annual ring growth of black spruce in some Alberta peatlands." Canadian Journal of Botany 67, no. 6 (June 1, 1989): 1885–89. http://dx.doi.org/10.1139/b89-239.

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The long-term relationship between climate and tree-ring growth in black spruce (Picea mariana (Mill.) B.S.P.) was determined in two peatland sites near Slave Lake, Alberta. At each site, 15 dominant – codominant black spruce were sampled for tree-ring growth at 30 cm height. The tree-ring indices for each site were related to precipitation and temperature data from Slave Lake. It was found that (i) tree-ring indices were positively correlated with June – August precipitation of the current year and of the 1st and 2nd years prior to the current year; (ii) June – August maximum temperatures of the current year and of the 1st and 2nd years prior to the current year were negatively correlated with tree-ring indices; (iii) tree-ring indices had a positive linear correlation with the June – August minimum temperature of the current year and polynomial correlations with June – August minimum temperatures of the 1st and 2nd years prior to the current year; and (iv) summer precipitation values greater than 325 mm probably had a negative impact upon the tree-ring growth. Maximum and minimum temperatures, however, were intercorrelated with precipitation. Key words: dendrochronology, climate, tree rings, peatlands, mire.

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Matos, Bárbara, Lurdes Borges Silva, Ricardo Camarinho, Armindo S. Rodrigues, Ruben Rego, Mariana Câmara, and Luís Silva. "Linking Dendrometry and Dendrochronology in the Dominant Azorean Tree Laurus azorica (Seub.) Franco." Forests 10, no. 7 (June 27, 2019): 538. http://dx.doi.org/10.3390/f10070538.

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As in many archipelagos, the Azorean primary forest was largely cleared and replaced by secondary forest and grassland, the Azorean tree Laurus azorica (Seub.) Franco being one of the dominant trees in the remaining natural forests. Dendrochronological and dendrometric studies in the Azores mainly focused on non-indigenous trees, either used for timber (e.g., Cryptomeria japonica D. Don) or considered as invasive (Pittosporum undulatum Vent.). Therefore, this study aims to describe the growth ring anatomy of L. azorica, and to understand the relationship between dendrometric traits (e.g., trunk diameter at breast height; tree height), and the number of growth rings. Growth ring anatomy was accessed by wood anatomical preparation of microcore samples while tree age estimation was based on growth ring counts in wood cores taken at breast height and at base. A total of 145 trees were sampled, resulting in 262 increment cores, at six representative stands of laurel forest in São Miguel Island (Azores). The wood anatomical analysis confirmed the presence of clear annual ring boundaries, and a high structural similarity towards Laurus novocanariensis Rivas Mart., Lousã, Fern.Prieto, E.Días, J.C.Costa & C.Aguiar. Age at tree base averaged 33 years, with 60% of the trees between 25 and 50 years old, and only about 15% above 50 years old. This suggests the existence of a secondary forest that is more recent than expected, probably due to human disturbance. The allometric models showed best fit when calculated by stand, suggesting the effect of local environmental conditions on growth rate. Radial growth rate was estimated at 0.68 cm.year−1. Given the known dominance of this species and the threats affecting natural forests, this baseline study will allow a better understanding of forest distribution and dynamics, and support a more effective forest management approach.

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Carvalho, Daniel Costa de, Marcos Gervasio Gervasio Pereira, Jair Figueiredo do Carmo, José Henrique Camargo Pace, Leonardo Davi Silveira Augusto Baptista da Silva, and João Vicente Figueiredo Latorraca. "Dendrochronology and growth of Copaifera langsdorffii wood in the vegetation dynamics of the Pirapitinga Ecological Station, state of Minas Gerais, Brazil." FLORESTA 48, no. 1 (June 6, 2018): 49. http://dx.doi.org/10.5380/rf.v48i1.49905.

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This study aims to build a chronology of the growth rings of Copaifera langsdorffii (copaíba) in order to understand the dynamics of vegetation types that occur on a river island in the Cerrado biome. For this purpose, we selected 30 trees of copaíba established in a vegetation of Mata Seca Sempre-Verde in the Pirapitinga Ecological Station (EEP), state of Minas Gerais, Brazil. Two radial samples from each tree were collected by an auger. The samples were treated by mechanical polishing for better visualization of the growth rings, and consequently further delineation and measurement. Later, the width of the growth rings was verified in order to generate a master time series of the specie. To check the influence of meteorological factors, we used the Pearson correlation (p < 0.05). The results showed that the population of copaíba in the EEP presented dendrochronologyc potential, which was confirmed by the high values of wide growth rings correlation within and between trees. The dendrochronologyc analysis revealed that copaíba trees were already present before the dam filling, but with lower population density than today. It was also possible to infer that the development of the vegetation type Mata Seca Sempre-Verde occurred since the decade of the 1970. The average sensitivity was enough to consider the species sensitive to environmental variations. Precipitation and temperature only influenced positively the growth rings in the transition from dry to wet seasons. The results revealed information about the dynamics of the local vegetation, elucidating the changes that occurred in the environment in which the population of copaíba is established.

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Wilczynski, S., and J. Skrzyszewski. "Dendrochronology of Scots pine (Pinus sylvestris L.) in the mountains of Poland." Journal of Forest Science 49, no. 3 (March 25, 2003): 95–105. http://dx.doi.org/10.17221/4684-jfs.

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In the area of southern Poland 33 pine stands growing at the altitudes from 350 to 1,200 m above sea level in the Carpathian and Sudeten Mountains were selected as the object of studies. Thirty-three site chronologies of tree-rings, representing each site were constructed. A decrease in the similarity of dendrochronological signal chronologies occurred with the growing distance between the sites. Correlation and convergence analysis and the Principal Components Analysis permitted the differentiation of two chronology groups: the Western (Sudeten) and the Eastern (Carpathian) ones. On the basis of the site chronologies regional chronologies for the Carpathian and Sudeten Mts. were constructed. The investigated pines from the two regions manifested great sensitivity to winter frost and in summer to the deficiency of heat and water. The chronologies were strongly integrated by the pattern of air temperatures, being differentiated by the pluvial conditions.

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Vázquez-González, Carla, Rafael Zas, Nadir Erbilgin, Scott Ferrenberg, Vicente Rozas, and Luis Sampedro. "Resin ducts as resistance traits in conifers: linking dendrochronology and resin-based defences." Tree Physiology 40, no. 10 (May 30, 2020): 1313–26. http://dx.doi.org/10.1093/treephys/tpaa064.

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Abstract Conifers have evolved different chemical and anatomical defences against a wide range of antagonists. Resin ducts produce, store and translocate oleoresin, a complex terpenoid mixture that acts as both a physical and a chemical defence. Although resin duct characteristics (e.g., number, density, area) have been positively related to biotic resistance in several conifer species, the literature reporting this association remains inconclusive. Axial resin ducts recorded in annual growth rings are an archive of annual defensive investment in trees. This whole-life record of defence investment can be analysed using standard dendrochronological procedures, which allows us to assess interannual variability and the effect of understudied drivers of phenotypic variation on resin-based defences. Understanding the sources of phenotypic variation in defences, such as genetic differentiation and environmental plasticity, is essential for assessing the adaptive potential of forest tree populations to resist pests under climate change. Here, we reviewed the evidence supporting the importance of resin ducts in conifer resistance, and summarized current knowledge about the sources of variation in resin duct production. We propose a standardized methodology to measure resin duct production by means of dendrochronological procedures. This approach will illuminate the roles of resin ducts in tree defence across species, while helping to fill pivotal knowledge gaps in plant defence theory, and leading to a robust understanding of the patterns of variation in resin-based defences throughout the tree’s lifespan.

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Hong, Wan, Jung Hun Park, Gyujun Park, Ki Suk Sung, Won Kyu Park, and Jong-Geol Lee. "Regional Offset of Radiocarbon Concentration and Its Variation in the Korean Atmosphere from AD 1650–1850." Radiocarbon 55, no. 2 (2013): 753–62. http://dx.doi.org/10.1017/s003382220005791x.

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A series of annual tree-ring measurements has been performed in order to reconstruct the radiocarbon concentration variation in the Korean atmosphere from AD 1650 to 1850. The absolute ages of the samples were determined using dendrochronology. Alpha-cellulose extraction was applied to prepare the tree-ring samples for precise 14C measurement. The 14C concentrations of the tree rings were then plotted with the dendrochronological ages and showed that during the period AD 1650–1850, the discrepancy in 14C concentration in the Korean atmosphere from IntCal data is small enough to use IntCal data without any further correction. This is nearly one third of the average offset of the 400 yr from AD 1250 to 1650. One of the probable causes for the regional offset around Korea is the contribution of 14C-depleted CO2 released from the northern Pacific Ocean, where old deep water upwells to the surface. It is likely that the release rate of 14C-depleted CO2 decreased due to the temperature change during the Little Ice Age.

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Mozeto, A. A., Peter Fritz, M. Z. Moreira, E. Vetter, Ramon Aravena, Eneas Salati, and R. J. Drimmie. "Growth Rates of Natural Amazonian Forest Trees Based on Radiocarbon Measurements." Radiocarbon 30, no. 1 (1988): 1–6. http://dx.doi.org/10.1017/s0033822200043903.

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Evergreen trees in the tropical rain forest of the Amazonas Basin can produce growth rings which are not necessarily related to annual events. Therefore, estimation of growth rate cannot be done by dendrochronology. This report presents a technique for determining the growth rate of these trees based on radiocarbon measurements of two segments of equal radial distance from the outer part of the tree trunk. The measured 14C activity is compared to local 14C fallout and growth rates are derived from models taking into account bomb 14C effects. Eleven trees from various parts of the Amazon Basin were analyzed. The average growth rates range from ca 5 to > 40 yr per centimeter corresponding to extrapolated ages from ca 60 to > 400 yr.

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De Micco, V., F. Campelo, M. De Luis, A. Bräuning, M. Grabner, G. Battipaglia, and P. Cherubini. "INTRA-ANNUAL DENSITY FLUCTUATIONS IN TREE RINGS: HOW, WHEN, WHERE, AND WHY?" IAWA Journal 37, no. 2 (July 7, 2016): 232–59. http://dx.doi.org/10.1163/22941932-20160132.

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Intra-annual density fluctuations (IADFs) in tree rings are generally considered structural anomalies caused by deviations from the “normal course” of xylogenesis during the growing season. This definition is based on the bias that, under “normal conditions”, cambial activity stops once a year. Each tree ring can thus be dated to one calendar year, which is one of the principles of dendrochronology. The formation of IADFs can be triggered directly by environmental changes, especially in precipitation and temperature, that affect cambial activity and cell differentiation. It can also be the result of limited photosynthesis, due to defoliation induced by biotic or abiotic constraints.Often indicated with alternative terms, IADFs were first described in the 1930s, and recently reported for many trees and shrubs from different ecosystems throughout the world, particularly for Mediterranean species. Different types of IADFs have been detected; their formation and structural properties depend on many factors including tree genotype, age, size, rooting depth, habitat, soil, climate, photosynthetic activity, and allocation strategies. Whether IADFs affect the adaptive capability of plants remains, however, unclear.We provide an overview of the main anatomical features of IADFs and their occurrence in tree rings from various environments and climatic regimes. We propose a simplified way of classifying them and discuss the hypotheses about their functional role and the factors triggering their formation. To understand the ecological role of IADFs better, we recommend a multidisciplinary approach, involving wood anatomy, dendroecology, and stable isotopes, which has already been applied for Mediterranean species. We conclude by considering that IADFs appear to be the “rule” rather than “anomalies” in some ecosystems where they help plants cope with fluctuating environmental conditions. Moreover, their anatomical structure represents a valuable proxy of past climatic conditions at a sub-seasonal resolution and may be relevant to adapt hydraulic functioning of living trees to changing climatic conditions.

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Wistuba, Małgorzata, Ireneusz Malik, and Janusz Badura. "Tree rings as an early warning against catastrophic landslides: Assessing the potential of dendrochronology for determining slope stability." Dendrochronologia 53 (February 2019): 82–94. http://dx.doi.org/10.1016/j.dendro.2018.12.002.

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Hakozaki, Masataka, Fusa Miyake, Toshio Nakamura, Katsuhiko Kimura, Kimiaki Masuda, and Mitsuru Okuno. "Verification of the Annual Dating of the 10th Century Baitoushan Volcano Eruption Based on an AD 774–775 Radiocarbon Spike." Radiocarbon 60, no. 1 (August 29, 2017): 261–68. http://dx.doi.org/10.1017/rdc.2017.75.

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AbstractThe so-called Millennium Eruption of Baitoushan Volcano is one of the largest of the Common Era but its date has been uncertain. Recently, Oppenheimer et al. (2017) reported the eruptive year as late AD 946 using a new method called carbon-14 spike matching. However, it is necessary to verify their result to confirm the eruptive year, since only one wood sample was used in their study. We verified the eruptive year by measuring 14C contents in tree rings from another wood sample buried during the Baitoushan eruption. We succeeded in reproducing the AD 774–775 14C spike (Miyake et al. 2012), and counted the number of rings from the outermost ring accompanied by bark to the ring possessing the AD 774–775 14C spike. We found the outermost ring was formed in AD 946. Our study supported the result of Oppenheimer et al. (2017), which makes the eruptive year conclusive. Also, we suggest that the 14C spike-matching method can be a prominent dating tool applicable to ancient woods that are difficult to date using the usual dendrochronology techniques.

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Timonen, Mauri, Kari Mielikäinen, and Samuli Helama. "Timberline tree-ring statistics examined through chronology stripping." Forestry Studies 56, no. 1 (June 1, 2012): 5–15. http://dx.doi.org/10.2478/v10132-012-0001-9.

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Abstract Tree-ring data is commonly used in forest science and dendrochronology. As the collected datasets represent restricted populations of theoretical infinite sample size, an interesting question deals with the sample selection that is carried out during the fieldwork and through the data analyses. This paper considers the latter issue, by statistically examining a recently completed Scots pine dataset of timberline tree-rings from Lapland (northern Finland). Following the detrending of individual ring-width series, the composition of the data was restricted using a pre-determined criteria of linear correlativity between the individual sample series and the master chronology (Rmaster). This procedure reduced both the number of sites and the sample size (i.e. the number of individual tree-ring series) and altered the tree-ring statistics of the remaining subset of the data in a systematic fashion. It was seen that the first-order autocorrelation, mean sensitivity and standard deviation all ascended with the uplifted Rmaster criterion. Conspicuously, such filtering also reduced the correlation between the resulting tree-ring chronology and climate parameter. The results indicated that the screening of the data will alter the chronology statistics in a way that may be artificially generated, irrelative to the predetermined sample selection criteria. We remain to assume that the most fundamental selection of data is attained through the cross-dating process.

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Journal articles on the topic 'Dendrochronology Tree-rings'

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