Advanced X-ray CT scanning can boost tree ring research for earth system sciences

AbstractBackground and AimsTree rings, as archives of the past and biosensors of the present, offer unique opportunities to study influences of the fluctuating environment over decades to centuries. As such, tree-ring-based wood traits are capital input for global vegetation models. To contribute to earth system sciences, however, sufficient spatial coverage is required of detailed individual-based measurements, necessitating large amounts of data. X-ray computed tomography (CT) scanning is one of the few techniques that can deliver such data sets.MethodsIncrement cores of four different temperate tree species were scanned with a state-of-the-art X-ray CT system at resolutions ranging from 60 μm down to 4.5 μm, with an additional scan at a resolution of 0.8 μm of a splinter-sized sample using a second X-ray CT system to highlight the potential of cell-level scanning. Calibration-free densitometry, based on full scanner simulation of a third X-ray CT system, is illustrated on increment cores of a tropical tree species.Key ResultsWe show how multiscale scanning offers unprecedented potential for mapping tree rings and wood traits without sample manipulation and with limited operator intervention. Custom-designed sample holders enable simultaneous scanning of multiple increment cores at resolutions sufficient for tree ring analysis and densitometry as well as single core scanning enabling quantitative wood anatomy, thereby approaching the conventional thin section approach. Standardized X-ray CT volumes are, furthermore, ideal input imagery for automated pipelines with neural-based learning for tree ring detection and measurements of wood traits.ConclusionsAdvanced X-ray CT scanning for high-throughput processing of increment cores is within reach, generating pith-to-bark ring width series, density profiles and wood trait data. This would allow contribution to large-scale monitoring and modelling efforts with sufficient global coverage.

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TREE-RING STUDIES IN INDIA PAST APPRAISAL, PRESENT STATUS AND FUTURE PROSPECTS

IAWA Journal ◽

10.1163/22941932-90000224 ◽

2009 ◽

Vol 30 (4) ◽

pp. 361-370 ◽

Cited By ~ 22

Author(s):

Amalava Bhattacharyya ◽

Santosh K. Shah

Keyword(s):

Tree Ring ◽

Tree Rings ◽

Tree Species ◽

Present Status ◽

Regional Climate ◽

Ring Width ◽

Climate Reconstruction ◽

Global Perspective ◽

Future Prospects ◽

The Himalaya

A large number of tree species, especially of conifers growing in the Himalaya and a few broad-leaved taxa in the peninsular region, have been dendrochronologically analyzed in India. This paper is a review providing information as regards the present status and future prospects of tree-ring research in India. Many trees are recorded to have datable tree rings but only some of them have been used for climate reconstruction and other aspects, e.g., glacial fluctuation or palaeo-seismic dating. In future not only ring width which is widely used so far, but also other tree-ring parameters need to be analyzed for a better understanding of the regional climate and its linkage with other climatic phenomena in a global perspective.

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Proxy Climatic Data from Tree Rings at Lake Louise, Alberta : A Preliminary Report

Géographie physique et Quaternaire ◽

10.7202/032597ar ◽

2007 ◽

Vol 39 (2) ◽

pp. 127-140 ◽

Cited By ~ 14

Author(s):

B. H. Luckman ◽

J. P. Hamilton ◽

L. A. Jozsa ◽

J. Gray

Keyword(s):

Tree Ring ◽

Tree Rings ◽

Preliminary Report ◽

Ring Width ◽

Summer Temperature ◽

Picea Engelmannii ◽

Climatic Data ◽

X Ray ◽

Preliminary Results ◽

Components Analysis

ABSTRACT Preliminary results are presented of studies using oxygen isotopes and tree-ring densitometry to derive proxy climatic data from Picea engelmannii and Abies Iasiocarpa in the Canadian Rockies. Significant correlations occur between mean annual temperatures and δ18O determinations from five year groups of tree rings from three trees. However, unexplained anomalies in these relationships indicate that ring-width effects may reduce this correlation in some cases and that further exploratory work is necessary. Indexed chronologies for the period 1705-1980 were developed for 15 tree-ring variables derived by X-ray densitometry from 16 Picea cores. Principal components analysis was used to identify three groups of highly inter-correlated variables related to ring width, earlywood density and latewood characteristics. Each group responds differently to climatic controls increasing the potential for development of proxy climatic data over ring-width measures alone. Transfer function development is incomplete but preliminary results for summer temperature (June and July, R2 = 0,46) and December-March precipitation (R2 = 0,40) are presented as examples. Using these equations preliminary reconstructions for the period 1710-1980 are presented.

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Drought signals inferred from ring-width and stable carbon isotope chronologies from Thuja occidentalis trees growing at their northwestern distribution limit, central Canada

Canadian Journal of Forest Research ◽

10.1139/x2012-012 ◽

2012 ◽

Vol 42 (3) ◽

pp. 517-531 ◽

Cited By ~ 5

Author(s):

Robert Au ◽

Jacques C. Tardif

Keyword(s):

Tree Ring ◽

Tree Rings ◽

Stable Carbon Isotopes ◽

Stable Carbon Isotope ◽

Ring Width ◽

Ring Formation ◽

Moisture Regime ◽

Stable Carbon ◽

Thuja Occidentalis ◽

Central Canada

Stable carbon isotopes (δ13C) fixed in tree rings are dependent upon environmental conditions. Old northern white-cedar ( Thuja occidentalis L.) trees were sampled at their northwestern limit of distribution in central Canada. The objectives of the study were (i) to investigate the association between tree-ring δ13C values and radial growth in addition to the response of these variables to climate, (ii) to assess site differences between two sites varying in moisture regime, and (iii) to compare tree-ring δ13C of T. occidentalis with that of other boreal tree species growing at the northern limit of their distribution in central Canada. Over 2500 tree rings comprised of 15 T. occidentalis trees were analyzed for δ13C. Annually resolved δ13C (1650–2006) and ring-width (1542–2006) chronologies were developed. During the year of ring formation, ring width was associated with spring and early-summer conditions, whereas δ13C was more indicative of overall summer conditions. However, compared with δ13C values, ring width was more often associated with climate conditions in the year prior to ring formation. Conditions conducive to moisture stress were important for both parameters. Although ring width and δ13C corresponded to the drought intervals of the 1790s, 1840s, 1890s, 1930s, and 1960–1970, ring width may be more responsive to prolonged drought than δ13C. Tree-ring δ13C could, however, provide important information regarding physiological adaptations to drought.

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Contrasting Signals of the Westerly Index and North Atlantic Oscillation over the Drought Sensitivity of Tree-Ring Chronologies from the Mediterranean Basin

Atmosphere ◽

10.3390/atmos11060644 ◽

2020 ◽

Vol 11 (6) ◽

pp. 644 ◽

Cited By ~ 1

Author(s):

Pablo Casas-Gómez ◽

Raúl Sánchez-Salguero ◽

Pedro Ribera ◽

Juan C. Linares

Keyword(s):

North Atlantic Oscillation ◽

Tree Ring ◽

North Atlantic ◽

Tree Species ◽

Ring Width ◽

Pinus Nigra ◽

Western Mediterranean ◽

Drought Severity ◽

Drought Sensitivity ◽

Westerly Index

Extreme drought events are becoming increasingly frequent and extended, particularly in Mediterranean drought-prone regions. In this sense, atmospheric oscillations patterns, such as those represented by the North Atlantic Oscillation (NAO) index and the Westerly Index (WI) have been widely proven as reliable proxies of drought trends. Here, we used the Standardized Precipitation–Evapotranspiration Index (SPEI), as a reliable indicator of drought, to investigate the drought sensitivity of tree-ring width data (TRW) from several long-lived tree species (Abies borisii-regis, Abies cilicica, Abies pinsapo, Cedrus atlantica, Cedrus libanii, Pinus nigra, Pinus heldreichii). NAO and WI relations with TRW were also investigated in order to identify potential non-stationary responses among those drought proxies. Our temporal and spatial analyses support contrasting Mediterranean dipole patterns regarding the drought sensitivity of tree growth for each tree species. The spatial assessment of NAO and WI relationships regarding SPEI and TRW showed on average stronger correlations westward with non-stationary correlations between annual WI index and TRW in all species. The results indicate that the drought variability and the inferred drought-sensitive trees species (e.g., C. atlantica) are related to the NAO and the WI, showing that TRW is a feasible proxy to long-term reconstructions of Westerly Index (WI) variability in the Western Mediterranean region. Spatial variability of drought severity suggests a complex association between NAO and WI, likely modulated by an east–west Mediterranean climate dipole.

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Dendrochronological analysis and growth patterns of Polylepis reticulata (Rosaceae) in the Ecuadorian Andes

IAWA Journal ◽

10.1163/22941932-40190240 ◽

2019 ◽

Vol 40 (2) ◽

pp. 331-S5 ◽

Cited By ~ 3

Author(s):

C. Alvites ◽

G. Battipaglia ◽

G. Santopuoli ◽

H. Hampel ◽

R.F. Vázquez ◽

...

Keyword(s):

Tree Ring ◽

Tree Rings ◽

Stand Structure ◽

Climatic Factors ◽

Southern Oscillation ◽

Ring Width ◽

Vapour Pressure Deficit ◽

Growth Patterns ◽

Tree Ring Width ◽

Sources Of Information

ABSTRACTRelict tree species in the Andean mountains are important sources of information about climate variability and climate change. This study deals with dendroclimatology and growth patterns in Polylepis reticulata Hieron., growing at high elevation (mean of 4000 m a.s.l.) in three sites of the Ecuadorian Andes. The aims of the research were: (i) characterizing tree-ring boundaries; (ii) describing tree-ring patterns of the study sites; (iii) investigating the relationships between climate and radial tree growth; and (iv) determining the spatial correlation between seasonal climatic factors and tree-ring width of P. reticulata. Tree rings were characterized by semi-ring porosity and slight differences in fibre wall thickness between latewood and subsequent earlywood. In all sampling sites, tree rings in heartwood were more clearly visible than in sapwood. Tree-ring width was more related to temperature than to precipitation, with growth being also affected by site conditions and stand structure, as well as other local factors. No significant relationships were found between tree-ring chronologies of P. reticulata and El Niño-Southern Oscillation (ENSO) and Vapour Pressure Deficit indices. The study highlights that there is not a clear driving climate factor for radial growth of P. reticulata. Additional research is needed to study growth dynamics of this species and the impacts of local environmental variables.

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A 3585-YEAR RING-WIDTH DATING CHRONOLOGY OF QILIAN JUNIPER FROM THE NORTHEASTERN QINGHAI-TIBETAN PLATEAU

IAWA Journal ◽

10.1163/22941932-90000226 ◽

2009 ◽

Vol 30 (4) ◽

pp. 379-394 ◽

Cited By ~ 20

Author(s):

Xuemei Shao ◽

Shuzhi Wang ◽

Haifeng Zhu ◽

Yan Xu ◽

Eryuan Liang ◽

...

Keyword(s):

Tibetan Plateau ◽

Tree Ring ◽

Tree Species ◽

Qaidam Basin ◽

Ring Width ◽

Northwestern China ◽

Tree Ring Width ◽

Living Tree ◽

Qilian Juniper

This article documents the development of a precisely dated and wellreplicated long regional tree-ring width dating chronology for Qilian juniper (Juniperus przewalskii Kom.) from the northeastern Qinghai- Tibetan Plateau. It involves specimens from 22 archeological sites, 24 living tree sites, and 5 standing snags sites in the eastern and northeastern Qaidam Basin, northwestern China. The specimens were cross-dated successfully among different groups of samples and among different sites. Based on a total of 1438 series from 713 trees, the chronology covers 3585 years and is the longest chronology by far in China. Comparisons with chronologies of the same tree species about 200 km apart suggest that this chronology can serve for dating purposes in a region larger than the study area. This study demonstrates the great potential of Qilian juniper for dendrochronological research.

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Tree-Ring Analyses can be Improved by Measurement of Component Widths and Densities

The Forestry Chronicle ◽

10.5558/tfc53091-2 ◽

1977 ◽

Vol 53 (2) ◽

pp. 91-95 ◽

Cited By ~ 1

Author(s):

J. Harry G. Smith

Keyword(s):

Tree Ring ◽

Tree Rings ◽

Tree Growth ◽

Annual Rings ◽

Sources Of Information ◽

X Ray ◽

Annual Variations ◽

Binocular Microscope ◽

Study Component ◽

Ray Methods

Measurement of component widths of annual rings by binocular microscope and of densities by X-ray methods have increased the accuracy of estimation of effects of various factors on tree growth. Sources of information and examples of uses of tree-ring analyses are discussed. Measurements of latewood and earlywood components of tree rings are used to illustrate longterm trends and annual variations about them. It is concluded that foresters should study component widths and densities of tree rings in order to learn more about manipulation of tree growth toward desired goals.

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First Amburana cearensis (Fabaceae) tree-ring chronology in Brazil in a dry forest shows great potential for climate reconstruction

10.5194/egusphere-egu2020-11379 ◽

2020 ◽

Author(s):

Milena Godoy-Veiga ◽

Giuliano Locosselli ◽

Lior Regev ◽

Elisabetta Boaretto ◽

Gregório Ceccantini

Keyword(s):

South America ◽

Tree Ring ◽

Negative Correlation ◽

Ring Width ◽

Dry Forest ◽

Tree Ring Width ◽

Wet Season ◽

Seasonally Dry ◽

Spatial Coverage ◽

Standard Tree

<p>Tree-ring chronologies are an excellent climate archive for their spatial and temporal resolution. While networks of chronologies have been built outside the tropics helping to understand past regional climate trends, tropical regions still lag behind in terms of spatial coverage. Dendrochronological studies, however, may succeed in seasonally dry tropical forests where the growing season is well defined. <em>Amburana cearensis</em>, found in both dry and wet forests in South America, is poorly explored for dendrochronological purposes, with no previous study in Brazil. Therefore, we sampled trees growing in a seasonally dry forest in a karstic area in Central-Eastern Brazil, under the South American Monsoon domain, in order to explore this species potential for dendroclimatological studies in the region. We build a tree-ring width chronology using 26 trees. We found a strong common growth signal among trees, with an r-bar of 0.51 and an average mean sensitivity of 0.50. The standard tree-ring width chronology showed a significant negative correlation with Vapor-Pressure Deficit during the entire wet season (0.54), negative correlation with temperature at the end of the wet season (0.45), and a positive correlation with the sum of precipitation during the wet season (0.46). Further stable isotopic analysis will provide additional records of climate variability in the region. Since Amburana cearensis occurs across most of the seasonally dry forests and savannas from South America, it has a great potential to be used to develop climate reconstructions and verify the effects of climate change currently affecting the region.</p>

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Retrospective analysis of growth A contribution to sustainable forest management in the tropics

IAWA Journal ◽

10.1163/22941932-20170173 ◽

2017 ◽

Vol 38 (3) ◽

pp. 297-S21 ◽

Cited By ~ 1

Author(s):

Neda Lotfiomran ◽

Michael Köhl

Keyword(s):

Forest Management ◽

Tropical Forests ◽

Tree Ring ◽

Tree Rings ◽

Tree Species ◽

Sustainable Forest Management ◽

Cedrela Odorata ◽

Tree Ring Analysis ◽

Hymenaea Courbaril ◽

Ring Analysis

Reliable information on tree growth is a prerequisite for sustainable forest management (SFM). However, in tropical forests its implementation is often hampered by insufficient knowledge of the growth dynamics of trees. Although tree ring analysis of tropical trees has a long history, its application for SFM has only recently been considered. In the current study, we illustrate both the potentials and limitations of a retrospective growth assessment by tree ring analysis under the prevailing tropical conditions in a Surinamese rain forest. For this purpose, 38 commercial tree species were screened and grouped into three categories according to the visibility of their tree ring boundaries: (I) tree rings absent or indistinct, (II) distinct but partially vague tree rings which enable approximate age estimation, (III) very distinct tree rings. In 22 out of 38 commercial tree species distinct to very distinct tree ring boundaries could be identified. The anatomy of tree ring boundaries was described following Worbes and Fichtler (2010). Four species with distinct growth rings, Cedrela odorata, Hymenaea courbaril, Pithecellobium corymbosum and Goupia glabra, were studied in greater detail. Time-series analysis was used to characterise their radial growth. From the tree ring width, the annual diameter increment and cumulative diameter growth were calculated to find long-term growth patterns. Pithecellobium corymbosum and partially Hymenaea courbaril followed a typical S-shaped growth curve. By contrast, Goupia glabra and Cedrela odorata did not exhibit an age-related decrease of growth, but showed a constant linear growth over their entire life span. If based on more sample trees, such data can provide target-oriented information for improving SFM in tropical forests.

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On the ‘Divergence Problem’ in the Alatau Mountains, Central Asia: A Study of the Responses of Schrenk Spruce Tree-Ring Width to Climate under the Recent Warming and Wetting Trend

Atmosphere ◽

10.3390/atmos10080473 ◽

2019 ◽

Vol 10 (8) ◽

pp. 473 ◽

Cited By ~ 3

Author(s):

Zhang ◽

Jiang ◽

Bagila ◽

Ainur ◽

...

Keyword(s):

Central Asia ◽

Tree Ring ◽

Tree Growth ◽

Tree Species ◽

Climatic Factors ◽

Ring Width ◽

Tree Ring Width ◽

Recent Warming ◽

Divergence Problem ◽

The Stability

The divergence problem, which manifests as an unstable response relationship between tree-ring growth and climatic factors under the background of global warming, poses a challenge to both the traditional theory of dendroclimatology and the reliability of climatic reconstructions based on tree-ring data. Although Schrenk spruce, as the dominant tree species in the Tianshan Mountains, is frequently applied in the dendrochronological studies, the understanding of the divergence problem of this tree species is still limited. This study conducted correlation analysis between climatic factors and tree-ring width chronologies from 51 living and healthy specimens of Schrenk spruce at sites of high and low elevation in the Alatau Mountains to determine the stability of the response. The results revealed that the tree-ring width of the spruce specimens was correlated positively with precipitation and correlated negatively with temperature. Although the variations of the two tree-ring chronologies were similar, the radial growth of the spruce at the low elevation was found more sensitive to climatic factors. Furthermore, the sensitivity of tree growth to climate demonstrated an obvious increase after an abrupt change of climate under the background of the recent warming and wetting trend. Increased drought stress, calculated based on climatic data, was regarded as the main reason for this phenomenon. The results supply the gap of the stability of climatic response of tree growth in Central Asia to some extent.

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