DendrochronologiaPub Date : 2025-05-04DOI: 10.1016/j.dendro.2025.126349
Quan Zhang , Yu Liu , Huiming Song , Lu Wang , Congxi Fang , Yifan Ma
{"title":"Spatial patterns and temporal evolution of tree radial growth responses to climate in the Tianshan Mountains","authors":"Quan Zhang , Yu Liu , Huiming Song , Lu Wang , Congxi Fang , Yifan Ma","doi":"10.1016/j.dendro.2025.126349","DOIUrl":"10.1016/j.dendro.2025.126349","url":null,"abstract":"<div><div>Understanding how tree growth in alpine forests in arid and semi-arid areas responds to climate variability is a crucial concern. We collected 1549 samples from 44 sites across the Tianshan Mountains and established a network of tree-ring width chronologies for <em>Picea schrenkiana</em>. Principal component analysis revealed spatial heterogeneity in tree radial growth in the western and eastern subregions of the Tianshan Mountains. We also found that precipitation from previous July to current June (before and early growing season) was a key driver of tree growth throughout the Tianshan Mountains, moisture availability in the April-October (growing season) was more limiting in the eastern region, which led to spatial heterogeneous responses of tree growth to climate. Following the transition from warm-wet to warm-dry conditions in 1998, tree growth responses to climate also shifted. The influence of precipitation in the pre-growing-season remained dominant, the impact of temperature during the growing season increased significantly. We also found that temperature suppressed tree growth in the western region through drought stress, while the limiting effect of precipitation on tree growth became more pronounced in the eastern region. Both spatial and temporal characteristics of tree growth responses to climate intensified with decreasing annual precipitation. Therefore, prioritizing moisture availability is imperative for effective forest management and ecological protection in the Tianshan Mountains.</div></div>","PeriodicalId":50595,"journal":{"name":"Dendrochronologia","volume":"92 ","pages":"Article 126349"},"PeriodicalIF":2.7,"publicationDate":"2025-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143936275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
DendrochronologiaPub Date : 2025-05-02DOI: 10.1016/j.dendro.2025.126346
Bingyun Du , Dongyou Zhang , Shengye Shan , Zhaopeng Wang , Yang Qiu , Taoran Luo , Xinrui Wang
{"title":"Impact of compound drought--heat stress on Mongolian Scots pine growth: A Copula-based analysis across precipitation gradients","authors":"Bingyun Du , Dongyou Zhang , Shengye Shan , Zhaopeng Wang , Yang Qiu , Taoran Luo , Xinrui Wang","doi":"10.1016/j.dendro.2025.126346","DOIUrl":"10.1016/j.dendro.2025.126346","url":null,"abstract":"<div><h3>Background</h3><div>Compound drought–heat events increasingly threaten forests, yet responses, especially across moisture gradients, remain poorly understood compared to single extremes. We assessed Mongolian Scots pine (<em>Pinus sylvestris var. mongolica</em>) radial growth responses to high-intensity compound drought–heat events (HICEs) across a precipitation gradient (low/MG, medium/TH, high/XL sites) in China’s northern Greater Khingan Mountains, focusing on precipitation’s modulating role.</div></div><div><h3>Methods</h3><div>Using dendrochronology (Standardized Ring-Width Index, RWI; 1958–2023 CE) and climate data (Palmer Drought Severity Index, PDSI; Vapor Pressure Deficit, VPD), we employed Copula functions to model the joint probability of May-July low PDSI and high VPD, generating a Compound Drought–Heat Severity Index (CDHSI). We identified HICEs (CDHSI <−1.6) and quantified differential growth responses using resilience metrics (resistance Rt, recovery Rc, resilience Rs).</div></div><div><h3>Results</h3><div>Mongolian Scots pine radial growth was primarily constrained by moisture stress, exhibiting significant negative correlations with May-July VPD (e.g., MG: <em>r</em>=−0.57; TH: <em>r</em>=−0.18) and a positive correlation with PDSI in the low-precipitation zone (MG: <em>r</em>=0.43). The Copula-derived CDHSI effectively captured compound stress (correlating with VPD <em>r</em>=−0.78, PDSI <em>r</em>=0.80) and identified nine HICEs, frequently coinciding with negative pointer years. HICEs significantly suppressed growth, most severely (<em>p</em><0.01) under low precipitation (MG), with significant multi-year growth differences (<em>p</em><0.05) compared to high precipitation (XL). Recovery strategies diverged: low-precipitation pines showed decreased resistance (Rt: 0.6→0.42) but increased recovery (Rc: 1.4→1.98) with event severity, while high-precipitation pines showed enhanced Rt, Rc, and Rs.</div></div><div><h3>Conclusions</h3><div>This first Copula-based regional assessment demonstrated significant HICE-induced growth inhibition in Mongolian Scots pine, strongly modulated by precipitation. Sites with low precipitation exhibited heightened sensitivity to HICEs, whereas high precipitation enhanced both resistance and recovery. These quantified findings address critical knowledge gaps regarding forest responses to compound stressors and provide a crucial foundation for developing adaptive forest management strategies under projected climate change.</div></div>","PeriodicalId":50595,"journal":{"name":"Dendrochronologia","volume":"92 ","pages":"Article 126346"},"PeriodicalIF":2.7,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143918325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
DendrochronologiaPub Date : 2025-04-30DOI: 10.1016/j.dendro.2025.126343
Louis Verschuren , Vladimir Matskovsky , Matthieu N. Boone , Luc Van Hoorebeke , Joris Van Acker , Tom De Mil , Valerie Trouet , Charlotte Pearson , Jorden De Bolle , Toon Gheyle , Jan Van den Bulcke
{"title":"X-ray micro-CT pipeline for large-scale tree-ring densitometry studies","authors":"Louis Verschuren , Vladimir Matskovsky , Matthieu N. Boone , Luc Van Hoorebeke , Joris Van Acker , Tom De Mil , Valerie Trouet , Charlotte Pearson , Jorden De Bolle , Toon Gheyle , Jan Van den Bulcke","doi":"10.1016/j.dendro.2025.126343","DOIUrl":"10.1016/j.dendro.2025.126343","url":null,"abstract":"<div><div>Tree-ring data provides essential insights into historical climate conditions and current ecosystem dynamics. Wood density measurements complement traditional tree-ring width series by extracting additional climatic information embedded within tree rings, with maximum latewood density serving as the gold standard for summer temperature reconstructions. However, the labor-intensive wood sample preparation required by conventional techniques is one of the main factors limiting the more widespread use of tree-ring densitometry. X-ray micro-computed tomography (X<em>μ</em>CT) offers a novel, non-destructive, 3D densitometry technique that enables the simultaneous study of tree-ring width and wood density at high resolution and with minimal sample preparation. Despite its potential, the lack of a streamlined and time-efficient X<em>μ</em>CT workflow has hindered its broader application in the past. Here we present a highly optimized X<em>μ</em>CT pipeline aimed at large-scale tree-ring densitometry studies, capable of processing large amounts of increment cores with a low demand for human labor time (2.2–5.4 min per 35 cm sample length). Key parts include large and efficient sample holders (16–48 samples per scan), optimized and standardized scan settings (helical X<em>μ</em>CT at 15, 30, and 60 <em>μ</em>m voxel size), and three custom software packages (facilitating scan processing, ring indication, and cross-dating). Overall, this X<em>μ</em>CT toolchain represents a significant leap forward in high-resolution tree-ring densitometry, enabling large-scale studies with a wide spatial extent, high replication, and/or long temporal range.</div></div>","PeriodicalId":50595,"journal":{"name":"Dendrochronologia","volume":"92 ","pages":"Article 126343"},"PeriodicalIF":2.7,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143923490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
DendrochronologiaPub Date : 2025-04-30DOI: 10.1016/j.dendro.2025.126347
Kexin Jin , Jia Yao , Yuxin Bai , Zhulin Li , Mengguo Nie , Xingxing Li , Xiaochun Wang
{"title":"Comparison of xylem anatomical traits among three maple species and their climate relationships across slope positions in northeast China","authors":"Kexin Jin , Jia Yao , Yuxin Bai , Zhulin Li , Mengguo Nie , Xingxing Li , Xiaochun Wang","doi":"10.1016/j.dendro.2025.126347","DOIUrl":"10.1016/j.dendro.2025.126347","url":null,"abstract":"<div><div><ul><li><span>•</span><span><div>Xylem anatomical characteristics vary among the three <em>Acer</em> species.</div></span></li></ul><ul><li><span>•</span><span><div>At different slope positions, a trade-off exists between hydraulic safety and efficiency in xylem anatomical characteristics.</div></span></li></ul></div><div><ul><li><span>•</span><span><div>The temperature and precipitation throughout the growing season (July-September) exert a significant impact on the xylem anatomical traits, and distinct discrepancies are observed in the response patterns across varying slope positions.</div></span></li></ul></div><div>The <em>Acer</em> genus is a major group in temperate forests of northeast China, but studies on how the xylem anatomical features of different <em>Acer</em> species respond to climate conditions are few. This study uses wood anatomy techniques to investigate the radial growth and xylem vessel features of <em>A. mandshuricum</em>, <em>A</em>. <em>tataricum</em> and <em>A</em>. <em>tegmentosum</em> at two slope positions in response to climate factors. The results shows that the ring width (RW) of <em>A. tegmentosum</em> is the widest, with large but few vessels. The RW of <em>A. tataricum</em> is the narrowest, with small but more vessels. The vessel density (VD) and theoretical water conductivity (Ks) of <em>A. mandshuricum</em> are significantly higher on middle slope than on downhill slope. The Dh of <em>A. tataricum</em> is significantly higher on the middle slope than on the downhill slope, but the VD was the opposite. The Ks and Dh of <em>A. tegmentosum</em> are significantly higher on the middle slope than on the downhill slope. However, the VD is significantly lower on the middle slope. The RW of <em>A. mandshuricum</em> is significantly correlated with water conditions from July to September. The Ks and Dh of <em>A. tegmentosum</em> are constrained by the monthly maximum temperature (T<sub>max</sub>) on the downhill slope, while the vessel characteristics on the middle slope are mainly positively correlated with T<sub>max</sub>. The RW of <em>A. tegmentosum</em> is positively correlated with monthly minimum temperature (T<sub>min</sub>) on the middle slope, while the RW of <em>A. tataricum</em> is inhibited by T<sub>max</sub>, and the Ks is affected by T<sub>min</sub>. This study provides an important scientific basis for understanding the mechanisms by which different slope positions and species of trees respond to climate conditions.</div></div>","PeriodicalId":50595,"journal":{"name":"Dendrochronologia","volume":"92 ","pages":"Article 126347"},"PeriodicalIF":2.7,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143912530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
DendrochronologiaPub Date : 2025-04-28DOI: 10.1016/j.dendro.2025.126345
Min-Seok Kim , Mauricio Fuentes , Hans W. Linderholm , Frida Lidman , Youngdae Koh , Chanhyuk Choi , Jee-Hoon Jeong
{"title":"Tree growth responses to summer temperature on the Korean Peninsula detected by tree-ring blue intensity","authors":"Min-Seok Kim , Mauricio Fuentes , Hans W. Linderholm , Frida Lidman , Youngdae Koh , Chanhyuk Choi , Jee-Hoon Jeong","doi":"10.1016/j.dendro.2025.126345","DOIUrl":"10.1016/j.dendro.2025.126345","url":null,"abstract":"<div><div>Tree-ring blue intensity (BI), a relatively new proxy using the amount of blue light reflected from tree-ring cores, has garnered considerable attention in dendroclimatology due to its effectiveness in capturing climate signals. While the application of BI in climate reconstructions is spreading across the world, it has not yet been fully explored in East Asia. In this pilot study, tree-ring width (TRW) and BI (earlywood BI, maximum latewood BI, and delta BI) chronologies were developed from Korean pine (<em>Pinus koraiensis</em> Siebold & Zucc.) on Mt. Seorak in the Korean Peninsula. While the BI chronologies developed in this study exhibited relatively weak series intercorrelations, they nonetheless captured significant and consistent summer temperature signals, demonstrating their dendroclimatological potential. In particular, the delta BI (DBI) chronology was well correlated with summer (July to August) mean temperature at both local and regional scales. In contrast to the TRW chronology, which failed to capture a consistent climate-related signal, the DBI chronology consistently retained the tree growth response to summer temperature variability from the early 20th century to the present. Further large-scale correlation analysis demonstrated that the DBI chronology can be used in the historical reconstruction of the circumglobal teleconnection pattern and the subtropical jet stream. These findings show that the application of the BI methodology can significantly enhance the ability of tree-ring data to capture climate signals that are not apparent in TRW in subtropical East Asia.</div></div>","PeriodicalId":50595,"journal":{"name":"Dendrochronologia","volume":"92 ","pages":"Article 126345"},"PeriodicalIF":2.7,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143912080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
DendrochronologiaPub Date : 2025-04-28DOI: 10.1016/j.dendro.2025.126342
Alan Crivellaro , Flavio Ruffinatto , Paola Nola , Renzo Motta , Michele Freppaz , Marta Monterin , Alma Piermattei
{"title":"Notes on the Larix/Picea wood identification problem: Dendrochronological and wood anatomical insights from a subfossil stem disk","authors":"Alan Crivellaro , Flavio Ruffinatto , Paola Nola , Renzo Motta , Michele Freppaz , Marta Monterin , Alma Piermattei","doi":"10.1016/j.dendro.2025.126342","DOIUrl":"10.1016/j.dendro.2025.126342","url":null,"abstract":"<div><div>The decades-old problem of distinguishing spruce (<em>Picea</em> sp.) from larch (<em>Larix</em> sp.) wood is still debated in wood identification. Although species-specific anatomical traits have been proposed to address this issue, their variable appearance and limited diagnostic power hinder reliable differentiation, particularly for archaeological wood samples. Finding a stem disk collected over a century ago from a glacial moraine deposit brought us to face the <em>Larix</em>/<em>Picea</em> identification problem again. Here, we skimmed the literature for wood anatomical features typical for each species and examined these traits in the subfossil wood disk. Key features assessed included heartwood and sapwood colour differences, earlywood-to-latewood transitions, tracheid pitting in radial walls, ray tracheid pit borders, the number of epithelial cells per resin canal, and the position of resin canals in rays. Additionally, we measured tree-ring widths to attempt dendrochronological dating of the disk. Tree-ring measurements enabled precise dating and revealed a quasi-decadal occurrence of narrow and light rings, indicative of cyclical larch budmoth (<em>Zeiraphera diniana</em> Gn.) infestations. Based on the presence of these characteristic budmoth rings and successful crossdating with 31 published and unpublished larch chronologies, compared to poor correlation with spruce chronologies, we conclusively identified the disk as <em>Larix decidua</em> Mill. However, our wood anatomical observations did not distinguish between spruce and larch reliably, suggesting that some features may vary with tree age and stem position. This highlights the need for further investigation with targeted sampling of living trees to validate the diagnostic utility of certain anatomical features.</div></div>","PeriodicalId":50595,"journal":{"name":"Dendrochronologia","volume":"92 ","pages":"Article 126342"},"PeriodicalIF":2.7,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143898976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
DendrochronologiaPub Date : 2025-04-28DOI: 10.1016/j.dendro.2025.126344
Justin T. Maxwell , Karen E. King , Grant L. Harley
{"title":"Removing the transition wood carryover effect from latewood blue intensity to improve climate signals from Tsuga canadensis in the eastern United States","authors":"Justin T. Maxwell , Karen E. King , Grant L. Harley","doi":"10.1016/j.dendro.2025.126344","DOIUrl":"10.1016/j.dendro.2025.126344","url":null,"abstract":"<div><div>Tree rings have long provided critical insights into past temperature variability and extremes, helping to contextualize recent warming trends. In recent decades, blue intensity (BI), a light-based reflectivity method, has become a widely used and cost-effective tool for estimating densiometric ring growth, often yielding stronger temperature signals than radial width measurements. However, certain aspects of BI remain underexplored, particularly the potential of a carryover effect from transition wood blue intensity (TBI) on latewood blue intensity (LWBI). In this study, we analyzed <em>Tsuga canadensis</em> (eastern hemlock) to determine whether removing the carryover effect of TBI improves the climate signal embedded within LWBI. Across 14 sites, TBI was significantly correlated with LWBI (mean <em>r</em> = 0.42, <em>p</em> < 0.01), suggesting a carryover effect. By removing the influence of TBI, the adjusted LWBI (LWBIa) reduced spring correlations (March-April; meanΔ = −0.05) while increasing correlations with August temperatures (meanΔ = +0.04) and growing season average Tmax (May-September; meanΔ = +0.04). LWBIa outperformed DeltaBI, with 93 % of sites showing improved correlations with August Tmax compared to 57 % for DeltaBI. However, LWBIa reduced correlations for September, limiting improvements in late summer averages (August-September). These findings demonstrate that adjusting LWBI by accounting for the carryover effect of TBI can improve temperature sensitivity for August and the growing season, potentially enhancing the accuracy of BI-based reconstruction models. Further studies are needed to evaluate this adjustment across other species and regions to fully assess its broader applicability.</div></div>","PeriodicalId":50595,"journal":{"name":"Dendrochronologia","volume":"91 ","pages":"Article 126344"},"PeriodicalIF":2.7,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143890690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
DendrochronologiaPub Date : 2025-04-21DOI: 10.1016/j.dendro.2025.126341
Onur Alkan
{"title":"Evaluating optimal percentile pairs for a Weibull-based diameter distribution in European black pine stands","authors":"Onur Alkan","doi":"10.1016/j.dendro.2025.126341","DOIUrl":"10.1016/j.dendro.2025.126341","url":null,"abstract":"<div><div>Understanding the diameter distribution of forest stands is essential for sustainable forest management, as it offers critical information about stand structure, growth dynamics, and potential timber yield. This study aims to identify the optimal percentile pairs and the most suitable modeling approaches for characterizing the diameter distribution of European black pine (<em>Pinus nigra</em> Arn.) stands in Türkiye via a three-parameter Weibull distribution. A Percentile-based recovery method was utilized for recovering the Weibull parameters. Eight percentile pairs (10th and 90th, 25th and 50th, 25th and 75th, 31st and 63rd, 31st and 95th, 50th and 75th, 50th and 95th, and 63rd and 75th percentiles) were evaluated through four different estimation approaches: ordinary least squares (OLS), seemingly unrelated regression (SUR), cumulative distribution function regression (CDFR), and stand table regression (STR). The results indicate that the percentile pair 31st and 63rd, when combined with CDFR, demonstrated the highest overall performance. In contrast, the 50th and 75th pairs combined with OLS and SUR demonstrated a lower performance. Among the estimation approaches, CDFR consistently achieves the best parameter recovery across most percentile pairs, whereas OLS and SUR often result in less accurate estimations. These findings suggest that specific percentile pairs, particularly 31st and 63rd, in combination with CDFR, offer superior characterization of diameters in black pine stands. This study provides a comprehensive evaluation of different percentile pairs and estimation approaches, contributing valuable information for forest management and modeling practices.</div></div>","PeriodicalId":50595,"journal":{"name":"Dendrochronologia","volume":"91 ","pages":"Article 126341"},"PeriodicalIF":2.7,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143873377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
DendrochronologiaPub Date : 2025-04-16DOI: 10.1016/j.dendro.2025.126338
Ernst van der Maaten , Gottfried Jetschke , Marieke van der Maaten-Theunissen
{"title":"Rethinking ‘clearcut’ methods: Embracing methodological diversity in pointer-year detection","authors":"Ernst van der Maaten , Gottfried Jetschke , Marieke van der Maaten-Theunissen","doi":"10.1016/j.dendro.2025.126338","DOIUrl":"10.1016/j.dendro.2025.126338","url":null,"abstract":"","PeriodicalId":50595,"journal":{"name":"Dendrochronologia","volume":"91 ","pages":"Article 126338"},"PeriodicalIF":2.7,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143843314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
DendrochronologiaPub Date : 2025-04-15DOI: 10.1016/j.dendro.2025.126340
Wenshuo Zhao , Junpeng Fu , Nick Wiesenberg , Benjamin V. Gaglioti , Gregory C. Wiles
{"title":"Improving the climate signal of tree-ring blue intensity of sub-fossil wood using hydrogen peroxide: An example from the gulf of Alaska, USA","authors":"Wenshuo Zhao , Junpeng Fu , Nick Wiesenberg , Benjamin V. Gaglioti , Gregory C. Wiles","doi":"10.1016/j.dendro.2025.126340","DOIUrl":"10.1016/j.dendro.2025.126340","url":null,"abstract":"<div><div>Blue intensity (BI) in tree-rings is a proxy for maximum latewood density (MXD) and has been widely used to reconstruct annual growing-season temperatures. BI records are more easily produced than MXD because their measurement requires fewer resources, however, there remain obstacles with samples that have color differences not related to wood density. Color differences between stained sub-fossil logs and unstained living trees in particular can cause systematic shifts in BI chronologies and thus limit paleoclimate reconstructions. Here we report on a promising treatment for sub-fossil wood destaining using hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) on mountain hemlock (<em>Tsuga mertensiana</em>) logs that were overrun by glaciers and preserved in sediments for several centuries from sites along the Gulf of Alaska (GOA). We found that the removal of this taphonomic wood staining is best accomplished using a 24-h bath in 12 % hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) at room temperature. The bleaching may have been achieved through the oxidative de-chelation of the Fe species from the Fe-tannate complex which is thought to be the source of wood color stain. BI measurements made before and after bleaching of 60 samples spanning 682 years indicate that the destaining leads to an improved inter-correlation of BI indices. This included a 26 % higher correlation for delta BI, 19 % higher for latewood and 7 % greater for earlywood BI. The standard deviation for delta BI measurement also increased after the treatment (0.071–0.090). We further tested the potential improvement of the climate signal after soaking by comparing an independent temperature reconstruction based on ring-widths through the 1050–1350 CE interval, which showed an improved climate signal for all BI parameters in terms of the variance of temperature explained after soaking. This includes a 19 % higher improvement for latewood BI, 5 % higher for delta BI and 12.5 % higher with the post-treatment earlywood BI. Furthermore, EPS and Rbar chronology statistics were significantly improved and the improvement is relatively insensitive to the standardization used. This work documents how H<sub>2</sub>O<sub>2</sub> destaining can improve the development of mountain hemlock BI tree-ring records and that it could potentially help in similar BI chronologies that include stained sub-fossil samples.</div></div>","PeriodicalId":50595,"journal":{"name":"Dendrochronologia","volume":"91 ","pages":"Article 126340"},"PeriodicalIF":2.7,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143867815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}