Pub Date : 2026-02-04DOI: 10.1016/j.quascirev.2026.109844
John T. White , John F.C. Johnson
In recent decades, Coastal Migration Theory has come to prominence in discussions of the initial peopling of the Americas. Southern Alaska would have, by necessity, played an important role in any coastal migration from Northeast Asia into North America, yet the archaeological record of southern coastal Alaska post-dates those of both temperate North America and interior Alaska. Groundbreaking research in British Columbia demonstrated the necessity of paleoenvironmental reconstruction, particularly understanding of sea-level dynamics, to investigations of early coastal occupations anywhere along the north Pacific Rim. Prince William Sound in southern Alaska has been identified as an area where stranded shorelines dating to the late Pleistocene should be preserved above modern sea level, yet traditional Chugach knowledge suggests persistent glaciation of the sound, possibly into the Holocene. Here we present our reconstruction efforts for this maritime region. While we successfully identified preserved uplifted marine deposits within the Sound, they date to the early-mid Holocene rather than the late Pleistocene and their preservation is contingent on specific localized tectonic influences, including some ongoing throughout the Holocene. This research demonstrates that locating ancient shorelines stranded above modern sea level in southern Alaska will be a complex process.
{"title":"Stranded shorelines in prince William sound, southern Alaska: Testing the applicability of pacific coast archaeological discovery models","authors":"John T. White , John F.C. Johnson","doi":"10.1016/j.quascirev.2026.109844","DOIUrl":"10.1016/j.quascirev.2026.109844","url":null,"abstract":"<div><div>In recent decades, Coastal Migration Theory has come to prominence in discussions of the initial peopling of the Americas. Southern Alaska would have, by necessity, played an important role in any coastal migration from Northeast Asia into North America, yet the archaeological record of southern coastal Alaska post-dates those of both temperate North America and interior Alaska. Groundbreaking research in British Columbia demonstrated the necessity of paleoenvironmental reconstruction, particularly understanding of sea-level dynamics, to investigations of early coastal occupations anywhere along the north Pacific Rim. Prince William Sound in southern Alaska has been identified as an area where stranded shorelines dating to the late Pleistocene should be preserved above modern sea level, yet traditional Chugach knowledge suggests persistent glaciation of the sound, possibly into the Holocene. Here we present our reconstruction efforts for this maritime region. While we successfully identified preserved uplifted marine deposits within the Sound, they date to the early-mid Holocene rather than the late Pleistocene and their preservation is contingent on specific localized tectonic influences, including some ongoing throughout the Holocene. This research demonstrates that locating ancient shorelines stranded above modern sea level in southern Alaska will be a complex process.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"377 ","pages":"Article 109844"},"PeriodicalIF":3.3,"publicationDate":"2026-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146102598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-31DOI: 10.1016/j.quascirev.2026.109833
Mingying Quan , Wei Zhong , Xiaojun Wang , Tianhang Li , Durui Lin , Limi Mao
Understanding vegetation dynamics and their driving mechanisms is crucial for predicting ecosystem responses. In this paper, we present a 46,300-year pollen record from the Dahu swamp (eastern Nanling Mountains, south China), so far the longest high-resolution lacustrine sequence in the subtropical monsoon region, to reconstruct vegetation dynamics and decipher different drivers. Biomization and principal component analyses were used for quantitative reconstruction of vegetation evolution history since ∼46.3 cal kyr BP.
During Marine Isotope Stage (MIS) 3b (∼46.3–41.2 cal kyr BP), warm and humid climate promoted the expansion of evergreen broadleaved forests (EBLF). A transition to cooler and drier climates in MIS 3c (∼41.2–26.8 cal kyr BP) favored the prevailing of deciduous broadleaved forests (DBLF) and herbaceous taxa. The Last Glacial Maximum (LGM, ∼26.8–17.4 cal kyr BP) of MIS 2 was featured by a mixed forest dominated by Fagus and Tsuga under cool-wet climate, sustained by weakened East Asia summer monsoon (EASM), persistent fog-cloud layers, and the topographic barrier effects of Nanling Mountains (NLM). Deglacial warming (∼17.4–12.2 cal kyr BP) triggered the expansion of thermophilic taxa (Cyclobalanopsis/Quercus (E)). The early Holocene (∼12.2–8.2 cal kyr BP) was marked by the dominance of EBLF under intensified EASM. Lake expansion and hygrophilous herbs prevailed during the mid-Holocene (∼8.2–4.2 cal kyr BP), whereas the late Holocene (∼4.2–0.6 cal kyr BP) was characterized by sparse vegetation cover (possibly open mosaic of forest and grassland), probably associated with cooling and intensified human activities especially since ∼2.8 cal kyr BP.
Spectral and wavelet analysis identifies orbital-scale precession-driven EASM variability (20.3-kyr cycle) since MIS 3b, modulated by tropical ocean-atmosphere oscillations (12.2-kyr cycle) and North Atlantic shifts (1.0-kyr cycles). By revealing how insolation-driven climate and topography together created cool, moist micro-refugia, the presence of Fagus and Tsuga forests during the LGM offers a basis for re-evaluating the hypothesis of extreme aridity in subtropical regions. This multi-scale analysis integrates orbital forcing, regional topography, and anthropogenic impacts, providing a framework for understanding subtropical forest resilience under climatic extremes.
了解植被动态及其驱动机制是预测生态系统响应的关键。本文利用迄今为止在亚热带季风区最长的高分辨率湖相序列——大湖沼泽（南岭东部）的46,300年花粉记录，重建植被动态，并解析不同的驱动因素。生物化和主成分分析用于定量重建自~ 46.3 cal kyr BP以来的植被演化史。在海洋同位素阶段（MIS） 3b (~ 46.3 ~ 41.2 cal kyr BP)，温暖湿润的气候促进了常绿阔叶林（EBLF）的扩张。MIS 3c （~ 41.2 ~ 26.8 cal kyr BP）向凉爽和干燥气候的过渡有利于落叶阔叶林（DBLF）和草本类群的盛行。mis2末次盛冰期（LGM，约26.8 ~ 17.4 cal kyr BP）以冷湿气候下的Fagus和Tsuga为主的混交林为特征，东亚夏季风（EASM）减弱，雾云层持续存在，南岭山脉（NLM）的地形阻隔作用持续存在。去冰变暖（~ 17.4-12.2 cal kyr BP）触发了嗜热类群（Cyclobalanopsis/Quercus (E)）的扩张。早全新世（~ 12.2-8.2 cal kyr BP）在强东亚寒流下以EBLF为主。在全新世中期（~ 8.2-4.2 cal kyr BP），湖泊扩张和亲湿草本植物盛行，而在全新世晚期（~ 4.2-0.6 cal kyr BP），植被覆盖稀疏（可能是森林和草地的开放花叶），这可能与降温和人类活动加剧有关，特别是自~ 2.8 cal kyr BP以来。光谱和小波分析确定了自MIS 3b以来轨道尺度岁差驱动的EASM变率（20.3 kyr周期），受到热带海洋-大气振荡（12.2 kyr周期）和北大西洋移动（1.0 kyr周期）的调制。通过揭示日照驱动的气候和地形如何共同创造凉爽潮湿的微型避难所，在LGM期间Fagus和Tsuga森林的存在为重新评估亚热带地区极端干旱的假设提供了基础。这种多尺度分析综合了轨道强迫、区域地形和人为影响，为了解极端气候下亚热带森林的恢复力提供了一个框架。
{"title":"Multi-scale drivers shaped the late Quaternary vegetation composition in eastern Nanling Mountains, subtropical China","authors":"Mingying Quan , Wei Zhong , Xiaojun Wang , Tianhang Li , Durui Lin , Limi Mao","doi":"10.1016/j.quascirev.2026.109833","DOIUrl":"10.1016/j.quascirev.2026.109833","url":null,"abstract":"<div><div>Understanding vegetation dynamics and their driving mechanisms is crucial for predicting ecosystem responses. In this paper, we present a 46,300-year pollen record from the Dahu swamp (eastern Nanling Mountains, south China), so far the longest high-resolution lacustrine sequence in the subtropical monsoon region, to reconstruct vegetation dynamics and decipher different drivers. Biomization and principal component analyses were used for quantitative reconstruction of vegetation evolution history since ∼46.3 cal kyr BP.</div><div>During Marine Isotope Stage (MIS) 3b (∼46.3–41.2 cal kyr BP), warm and humid climate promoted the expansion of evergreen broadleaved forests (EBLF). A transition to cooler and drier climates in MIS 3c (∼41.2–26.8 cal kyr BP) favored the prevailing of deciduous broadleaved forests (DBLF) and herbaceous taxa. The Last Glacial Maximum (LGM, ∼26.8–17.4 cal kyr BP) of MIS 2 was featured by a mixed forest dominated by <em>Fagus</em> and <em>Tsuga</em> under cool-wet climate, sustained by weakened East Asia summer monsoon (EASM), persistent fog-cloud layers, and the topographic barrier effects of Nanling Mountains (NLM). Deglacial warming (∼17.4–12.2 cal kyr BP) triggered the expansion of thermophilic taxa (<em>Cyclobalanopsis/Quercus</em> (E)). The early Holocene (∼12.2–8.2 cal kyr BP) was marked by the dominance of EBLF under intensified EASM. Lake expansion and hygrophilous herbs prevailed during the mid-Holocene (∼8.2–4.2 cal kyr BP), whereas the late Holocene (∼4.2–0.6 cal kyr BP) was characterized by sparse vegetation cover (possibly open mosaic of forest and grassland), probably associated with cooling and intensified human activities especially since ∼2.8 cal kyr BP.</div><div>Spectral and wavelet analysis identifies orbital-scale precession-driven EASM variability (20.3-kyr cycle) since MIS 3b, modulated by tropical ocean-atmosphere oscillations (12.2-kyr cycle) and North Atlantic shifts (1.0-kyr cycles). By revealing how insolation-driven climate and topography together created cool, moist micro-refugia, the presence of <em>Fagus</em> and <em>Tsuga</em> forests during the LGM offers a basis for re-evaluating the hypothesis of extreme aridity in subtropical regions. This multi-scale analysis integrates orbital forcing, regional topography, and anthropogenic impacts, providing a framework for understanding subtropical forest resilience under climatic extremes.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"376 ","pages":"Article 109833"},"PeriodicalIF":3.3,"publicationDate":"2026-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-29DOI: 10.1016/j.quascirev.2026.109813
Isabeau A. Bertrix , Hisashi Sato , Nicolas Viovy , Hans Renssen , Didier M. Roche
The period of the early Holocene in Europe is marked by climate warming as Earth comes out of the last glacial period and is followed by the emergence of agriculture and animal husbandry in the second half of the period. Increased human influence had profound impacts on the land surface, but the Holocene climate evolution also drove some changes that are intertwined with it. Deciphering the role of each in the vegetation evolution is becoming more difficult as one progresses to the earlier parts of the Holocene here human induced impacts were fainter. Within this general context, we aim at understanding how much Dynamical Vegetation Models (DGVMs) differ in their representation of Potential Natural Vegetation (PNV) in Europe during the mid-to late Holocene (8.5 k.a. BP to 1900 A. D.). We ran three different DGVMs, SEIB-DGVM, ORCHIDEE-DGVM and CARAIB, in Europe, for six time-slices and forced them with identical climatic imputs obtained from the iLOVECLIM Earth system model (downscaled and bias-corrected). Results are then compared with pollen-based reconstructions from the TERRANOVA database. Overall, the three models have a similar performance in representing the pollen-derived vegetation cover at the european scale. However, their results are largely different at regional scales, particularly in mountainous areas and in boreal regions. They also show a very large spread in simulated PFT diversity at the grid cell scale, highlighting the impact of each model's internal dynamics on the results. On a global scale, they all agree on a decreasing match of their results with pollen base reconstructions over time, indicating - as expected - an increase of the human pressure on the landscape.
{"title":"Holocene potential natural vegetation in Europe: Evaluating the model spread with three dynamical vegetation models","authors":"Isabeau A. Bertrix , Hisashi Sato , Nicolas Viovy , Hans Renssen , Didier M. Roche","doi":"10.1016/j.quascirev.2026.109813","DOIUrl":"10.1016/j.quascirev.2026.109813","url":null,"abstract":"<div><div>The period of the early Holocene in Europe is marked by climate warming as Earth comes out of the last glacial period and is followed by the emergence of agriculture and animal husbandry in the second half of the period. Increased human influence had profound impacts on the land surface, but the Holocene climate evolution also drove some changes that are intertwined with it. Deciphering the role of each in the vegetation evolution is becoming more difficult as one progresses to the earlier parts of the Holocene here human induced impacts were fainter. Within this general context, we aim at understanding how much Dynamical Vegetation Models (DGVMs) differ in their representation of Potential Natural Vegetation (PNV) in Europe during the mid-to late Holocene (8.5 k.a. BP to 1900 A. D.). We ran three different DGVMs, SEIB-DGVM, ORCHIDEE-DGVM and CARAIB, in Europe, for six time-slices and forced them with identical climatic imputs obtained from the iLOVECLIM Earth system model (downscaled and bias-corrected). Results are then compared with pollen-based reconstructions from the TERRANOVA database. Overall, the three models have a similar performance in representing the pollen-derived vegetation cover at the european scale. However, their results are largely different at regional scales, particularly in mountainous areas and in boreal regions. They also show a very large spread in simulated PFT diversity at the grid cell scale, highlighting the impact of each model's internal dynamics on the results. On a global scale, they all agree on a decreasing match of their results with pollen base reconstructions over time, indicating - as expected - an increase of the human pressure on the landscape.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"376 ","pages":"Article 109813"},"PeriodicalIF":3.3,"publicationDate":"2026-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-29DOI: 10.1016/j.quascirev.2026.109843
Liva Trasune , J Sakari Salonen , Normunds Stivrins , Leeli Amon , Migle Stancikaite , Laura Gedminiene , Siim Veski , Frederik Schenk
Late-Quaternary disruptions of the Atlantic Meridional Overturning Circulation (AMOC) have been linked to profound impacts on local and regional climate as well as vegetation. Temperature seasonality patterns during these AMOC events, most notably during the Younger Dryas, are not yet fully understood, as studies have shown two possible scenarios: overall cooling patterns in Younger Dryas, or warm summers with extreme winter cooling. Here we assess the seasonal temperature trends of late-Quaternary weak AMOC states in Northern Europe, based on new quantitative pollen- and plant macrofossil-based January and July temperature reconstructions using multi-method ensemble reconstruction approaches. For plant macrofossils, we implement a “dynamic” calibration approach, where a spatial extent of the modern calibration region varies based on an independent proxy for the past continentality regime. This allows the reconstruction to algorithmically select the most representative modern calibration region for each time slice. We find an indication that abrupt AMOC weakening is associated with winter-dominated cooling of up to 10 °C but relatively stable summers.
{"title":"High temperature seasonality as a signature of late-Quaternary AMOC weakening in Northern Europe","authors":"Liva Trasune , J Sakari Salonen , Normunds Stivrins , Leeli Amon , Migle Stancikaite , Laura Gedminiene , Siim Veski , Frederik Schenk","doi":"10.1016/j.quascirev.2026.109843","DOIUrl":"10.1016/j.quascirev.2026.109843","url":null,"abstract":"<div><div>Late-Quaternary disruptions of the Atlantic Meridional Overturning Circulation (AMOC) have been linked to profound impacts on local and regional climate as well as vegetation. Temperature seasonality patterns during these AMOC events, most notably during the Younger Dryas, are not yet fully understood, as studies have shown two possible scenarios: overall cooling patterns in Younger Dryas, or warm summers with extreme winter cooling. Here we assess the seasonal temperature trends of late-Quaternary weak AMOC states in Northern Europe, based on new quantitative pollen- and plant macrofossil-based January and July temperature reconstructions using multi-method ensemble reconstruction approaches. For plant macrofossils, we implement a “dynamic” calibration approach, where a spatial extent of the modern calibration region varies based on an independent proxy for the past continentality regime. This allows the reconstruction to algorithmically select the most representative modern calibration region for each time slice. We find an indication that abrupt AMOC weakening is associated with winter-dominated cooling of up to 10 °C but relatively stable summers.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"376 ","pages":"Article 109843"},"PeriodicalIF":3.3,"publicationDate":"2026-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-29DOI: 10.1016/j.quascirev.2026.109842
Savvas Paradeisis-Stathis , Matthew N. Waters , Debra A. Willard , Richard S. Vachula
Ecological pressures on aquatic ecosystems have increased over recent centuries due to human activities and climate change. However, contextualizing ecosystem deterioration is often challenging due to limited knowledge of environmental changes over millennial timescales. Subtropical Carolina bays in North Carolina, USA, have remained unglaciated, preserving paleolimnological records that extend back to the last glacial period. Here, we analyzed a sediment core from the ecologically rich Lake Waccamaw spanning more than 28,000 years for aquatic proxies of nutrients, photosynthetic pigments, cyanotoxins, carbon isotopes, and terrestrial proxies of pollen and charcoal. The study explored paleolimnological changes in the aquatic environment connected to land changes and climate during the late Quaternary in the southeastern Atlantic Coastal Plain. Results reveal that while current levels of colonial cyanobacteria are high, past levels of cyanobacteria, other primary producers, and cyanotoxins were higher under natural climate variability. Abrupt ecosystem responses to increasing trophic conditions during Interstadial 3 (27.8–26.4 cal ka BP) and the early Holocene (11.4–7 cal ka BP) were marked by increases in primary producer abundance, deciduous vegetation expansion, and fire activity. Cyanobacteria remained dominant throughout the record, with colonial forms prevailing during the Holocene. Increases in pigment concentrations aligned with Quercus and were primarily driven by hydroclimatic variability and nutrient stoichiometry. Transitions between Pinus and Quercus pollen matched stadials and interstadials in the δ18Ο record from the North Greenland Ice Core Project (NGRIP). This study highlights the value of multi-proxy millennial-scale paleolimnological records for understanding aquatic ecosystem responses to climate conditions during the late Pleistocene.
近几个世纪以来，由于人类活动和气候变化，水生生态系统面临的生态压力有所增加。然而，由于对千年时间尺度上的环境变化的认识有限，将生态系统退化置于背景下往往具有挑战性。美国北卡罗来纳州的亚热带卡罗莱纳湾一直未被冰川覆盖，保存着可追溯到末次冰期的古湖泊学记录。在这里，我们分析了来自生态丰富的Waccamaw湖的沉积物岩心，该岩心跨越了28,000多年，以获取营养物质、光合色素、蓝藻毒素、碳同位素的水生代用物，以及花粉和木炭的陆地代用物。本研究探讨了大西洋东南沿海平原晚第四纪与陆地变化和气候相关的水环境古湖泊学变化。结果显示，虽然目前的群落蓝藻水平很高，但在自然气候变化下，过去的蓝藻、其他初级生产者和蓝藻毒素水平较高。在过渡期3 （27.8-26.4 cal ka BP）和全新世早期（11.4-7 cal ka BP），生态系统对营养条件增加的突变响应以初级生产者丰度增加、落叶植被扩张和火灾活动为特征。蓝藻在整个记录中一直占主导地位，在全新世期间以殖民地形式盛行。色素浓度的增加与栎属植物一致，主要由水文气候变异和营养化学计量学驱动。在北格陵兰冰芯项目(NGRIP) δ18Ο记录中，松树和栎树花粉之间的过渡与地坪和地坪间相匹配。本研究强调了千年代用古湖泊记录对了解晚更新世水生生态系统对气候条件的响应的价值。
{"title":"Cyanobacteria and aquatic ecosystem dynamics across 28,000 years of environmental changes in subtropical North America","authors":"Savvas Paradeisis-Stathis , Matthew N. Waters , Debra A. Willard , Richard S. Vachula","doi":"10.1016/j.quascirev.2026.109842","DOIUrl":"10.1016/j.quascirev.2026.109842","url":null,"abstract":"<div><div>Ecological pressures on aquatic ecosystems have increased over recent centuries due to human activities and climate change. However, contextualizing ecosystem deterioration is often challenging due to limited knowledge of environmental changes over millennial timescales. Subtropical Carolina bays in North Carolina, USA, have remained unglaciated, preserving paleolimnological records that extend back to the last glacial period. Here, we analyzed a sediment core from the ecologically rich Lake Waccamaw spanning more than 28,000 years for aquatic proxies of nutrients, photosynthetic pigments, cyanotoxins, carbon isotopes, and terrestrial proxies of pollen and charcoal. The study explored paleolimnological changes in the aquatic environment connected to land changes and climate during the late Quaternary in the southeastern Atlantic Coastal Plain. Results reveal that while current levels of colonial cyanobacteria are high, past levels of cyanobacteria, other primary producers, and cyanotoxins were higher under natural climate variability. Abrupt ecosystem responses to increasing trophic conditions during Interstadial 3 (27.8–26.4 cal ka BP) and the early Holocene (11.4–7 cal ka BP) were marked by increases in primary producer abundance, deciduous vegetation expansion, and fire activity. Cyanobacteria remained dominant throughout the record, with colonial forms prevailing during the Holocene. Increases in pigment concentrations aligned with <em>Quercus</em> and were primarily driven by hydroclimatic variability and nutrient stoichiometry. Transitions between <em>Pinus</em> and <em>Quercus</em> pollen matched stadials and interstadials in the δ<sup>18</sup>Ο record from the North Greenland Ice Core Project (NGRIP). This study highlights the value of multi-proxy millennial-scale paleolimnological records for understanding aquatic ecosystem responses to climate conditions during the late Pleistocene.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"376 ","pages":"Article 109842"},"PeriodicalIF":3.3,"publicationDate":"2026-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-28DOI: 10.1016/j.quascirev.2026.109835
Jie Li , Kai Lu , Shixiong Yang , Zhuo Zheng , Qiuchi Wan , Gayan Bandara , Chuanxiu Luo , Zhongbo Wang
During the last glacial period, there has been controversy over whether the exposed area of the East China Sea (ECS) continental shelf was a vast expanse of grassland or a dense forest. So far, direct paleovegetation and paleoenvironmental evidence over the stages from MIS 4 to MIS 2 on this shelf has been scarce. Moreover, the exposed continental shelf since ca. 60 ka has been hypothesized as a potential migratory corridor for Homo sapiens entering East Asia during the Late Pleistocene. This makes the study of the paleovegetation in the exposed continental shelf areas even more important. The present study is based on a high-resolution, well-dated palynological and sedimentological dataset obtained from core TBF-1, collected from the outer ECS continental shelf, spanning the past 71,000 years. Our results demonstrate a distinct vegetational response to global sea-level fluctuations and concomitant monsoon variability. During the lowstand intervals of MIS 4 and MIS 2 (including the Last Glacial Maximum), the exposed ECS shelf was dominated by a cool, dry temperate grassland biome, characterized by high abundance of herbs such as Artemisia, Poaceae, and Chenopodiaceae, alongside substantial wetland communities indicated by Cyperaceae and Typha. In contrast, the milder conditions of MIS 3 supported a heterogeneous open-forest landscape comprising temperate deciduous broadleaved forests, such as Quercus, Fagus, and Juglans, interspersed with persistent grasslands. These extensive grasslands and associated wetlands formed a vast coastal plain that connected mainland China to the Korean Peninsula and the Japanese archipelago, providing critical resources such as freshwater, game, and traversable terrain for early human foragers. Collectively, these findings provide the first direct paleoecological evidence that the exposed ECS shelf constituted a favorable and viable ecosystem during the last glacial period, thereby substantiating the hypothesis that it served as a crucial conduit facilitating the initial dispersal of early modern humans into East Asia.
末次冰期，东海大陆架暴露区是广阔的草原还是茂密的森林一直存在争议。迄今为止，该陆架在MIS 4 - MIS 2阶段的古植被和古环境的直接证据很少。此外，约60ka以来暴露的大陆架被假设为智人在晚更新世进入东亚的潜在迁徙通道。这使得对裸露大陆架地区古植被的研究显得更加重要。目前的研究基于一个高分辨率的、年代确定的孢粉学和沉积学数据集，该数据集收集自外大陆架的TBF-1核心，跨越了71000年。我们的研究结果表明，植被对全球海平面波动和伴随的季风变化有明显的响应。在MIS 4和MIS 2低潮期（包括末次盛冰期），暴露的ECS陆架以凉爽、干温带的草地生物群系为主，以蒿科、禾本科和藜科等草本植物的丰富度为特征，同时还有以莎草科和Typha为特征的大量湿地群落。相比之下，MIS 3较温和的条件支持异质性开放森林景观，包括温带落叶阔叶林，如栎、Fagus和Juglans，点缀着持久的草原。这些广阔的草原和相关的湿地形成了广阔的沿海平原，将中国大陆与朝鲜半岛和日本群岛连接起来，为早期人类觅食者提供了淡水、猎物和可穿越的地形等重要资源。总的来说，这些发现提供了第一个直接的古生态学证据，表明暴露的ECS陆架在末次冰期构成了一个有利的、可行的生态系统，从而证实了它是促进早期现代人类最初向东亚扩散的关键渠道的假设。
{"title":"Expansion of grassland/open woodland across the East China Sea shelf since MIS 4 facilitated the early human dispersal","authors":"Jie Li , Kai Lu , Shixiong Yang , Zhuo Zheng , Qiuchi Wan , Gayan Bandara , Chuanxiu Luo , Zhongbo Wang","doi":"10.1016/j.quascirev.2026.109835","DOIUrl":"10.1016/j.quascirev.2026.109835","url":null,"abstract":"<div><div>During the last glacial period, there has been controversy over whether the exposed area of the East China Sea (ECS) continental shelf was a vast expanse of grassland or a dense forest. So far, direct paleovegetation and paleoenvironmental evidence over the stages from MIS 4 to MIS 2 on this shelf has been scarce. Moreover, the exposed continental shelf since ca. 60 ka has been hypothesized as a potential migratory corridor for <em>Homo sapiens</em> entering East Asia during the Late Pleistocene. This makes the study of the paleovegetation in the exposed continental shelf areas even more important. The present study is based on a high-resolution, well-dated palynological and sedimentological dataset obtained from core TBF-1, collected from the outer ECS continental shelf, spanning the past 71,000 years. Our results demonstrate a distinct vegetational response to global sea-level fluctuations and concomitant monsoon variability. During the lowstand intervals of MIS 4 and MIS 2 (including the Last Glacial Maximum), the exposed ECS shelf was dominated by a cool, dry temperate grassland biome, characterized by high abundance of herbs such as <em>Artemisia</em>, Poaceae, and Chenopodiaceae, alongside substantial wetland communities indicated by Cyperaceae and <em>Typha</em>. In contrast, the milder conditions of MIS 3 supported a heterogeneous open-forest landscape comprising temperate deciduous broadleaved forests, such as <em>Quercus</em>, <em>Fagus</em>, and <em>Juglans</em>, interspersed with persistent grasslands. These extensive grasslands and associated wetlands formed a vast coastal plain that connected mainland China to the Korean Peninsula and the Japanese archipelago, providing critical resources such as freshwater, game, and traversable terrain for early human foragers. Collectively, these findings provide the first direct paleoecological evidence that the exposed ECS shelf constituted a favorable and viable ecosystem during the last glacial period, thereby substantiating the hypothesis that it served as a crucial conduit facilitating the initial dispersal of early modern humans into East Asia.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"376 ","pages":"Article 109835"},"PeriodicalIF":3.3,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-28DOI: 10.1016/j.quascirev.2026.109821
Paul D. Henne , Susann Stolze , Natalie M. Kehrwald , Becky Brice , Craig D. Allen
Mountain forests and woodlands in semiarid regions of the world are threatened by climatic change and other human impacts. In the southwestern USA, climate and culturally driven changes to the structure and fire regimes of dry coniferous forests over recent centuries are well documented by tree-ring archives. However, the roles of climate and people as drivers of millennial-scale changes are less understood. We present a new record of vegetation dynamics and regional fire activity inferred from pollen, microscopic charcoal, and sediment geochemistry from Santa Fe Lake, NM (3532 m a.s.l.), the southernmost natural lake in the Rocky Mountains. Declining elemental intensities (e.g., Ti, Fe, Si) record local deglaciation after 14,000 cal yr BP followed by upslope expansion of trees indicated by increasing Pinus and Picea pollen percentages as the climate warmed during the Late Glacial. Cool, dry growing seasons probably limited the establishment of dense forests until after 12,200 cal yr BP when we hypothesize that Pinus ponderosa (ponderosa pine) expanded regionally (i.e., within 10–100 km) due to continued warming and a possible increase in monsoonal precipitation. Subalpine forests established near Santa Fe Lake by 10,300 cal yr BP as indicated by abundant conifer stomates and increasing Picea and Pinus aristata pollen percentages, which are highest after 5100 cal yr BP. Increasing Juniperus-type, Quercus, and Pinus edulis-type pollen record changes in vegetation belts at lower elevations after 10,300 cal yr BP. Maize pollen, an unambiguous indicator of Puebloan agriculture, first appears at 800 cal yr BP (1150 cal yr CE) and is present through 1600 cal yr CE when Spanish colonization brought cultural upheaval and population loss to local indigenous communities. Regional fire activity, inferred from microscopic charcoal influx, remained relatively constant for most of our record. However, average microscopic charcoal influx more than doubled relative to the rest of the Holocene during the last 2000 years, with the highest influx after 1550 cal yr BP (400 cal yr CE). The increased influx of microscopic charcoal coincides with archaeological evidence for dramatic regional population growth in the northern Rio Grande region and probably reflects extensive cultural burning associated with the development of an agricultural economy. Although climate was an important driver of vegetation change and fire regimes in the mountains of the southwestern USA during the Holocene, our results suggest that human impacts on regional burning during the last 2000 years far exceeded earlier climate-driven variation.
世界半干旱地区的山林和林地受到气候变化和其他人类影响的威胁。在美国西南部，近几个世纪以来，树木年轮档案很好地记录了气候和文化驱动的干燥针叶林结构和火灾制度的变化。然而，人们对气候和人类作为千年尺度变化驱动因素的作用知之甚少。本文利用落矶山脉最南端的天然湖泊圣达菲湖（3532 m a.s.l.）的花粉、微观木炭和沉积物地球化学资料，对植被动态和区域火灾活动进行了新的记录。元素强度（如Ti、Fe、Si）的下降记录了14000 calyr BP之后的局部冰川消退，随后随着晚冰期气候变暖，松树和云杉花粉百分比的增加表明树木的上坡扩张。凉爽干燥的生长季节可能限制了茂密森林的建立，直到12,200 calyr BP之后，我们假设由于持续变暖和季风降水可能增加，黄松（ponderosa）在区域内（即10-100公里内）扩张。圣达菲湖附近亚高山森林在10300 calyr BP形成，针叶林丰富，云杉和马斯托塔松花粉比例增加，在5100 calyr BP后最高。10300 calyr BP后，低海拔植被带中柏、栎、松花粉的增加记录了植被带的变化。玉米花粉是普韦布洛人农业的明确指标，最早出现在公元前800年（公元1150年），并一直存在到公元1600年，当时西班牙殖民给当地土著社区带来了文化动荡和人口损失。区域火灾活动，从微观木炭流入推断，在我们的大部分记录中保持相对恒定。然而，在过去的2000年里，相对于全新世的其他时间，平均微观木炭流入增加了一倍以上，在1550 cal yr BP （400 cal yr CE）之后流入最多。微观木炭的增加与北部里约热内卢Grande地区人口急剧增长的考古证据相吻合，可能反映了与农业经济发展有关的广泛的文化燃烧。尽管气候是全新世期间美国西南部山区植被变化和火灾状况的重要驱动因素，但我们的研究结果表明，过去2000年人类对区域燃烧的影响远远超过早期气候驱动的变化。
{"title":"Millennial-scale climatic and cultural impacts on vegetation and fire at the southern edge of the Rocky Mountains, USA","authors":"Paul D. Henne , Susann Stolze , Natalie M. Kehrwald , Becky Brice , Craig D. Allen","doi":"10.1016/j.quascirev.2026.109821","DOIUrl":"10.1016/j.quascirev.2026.109821","url":null,"abstract":"<div><div>Mountain forests and woodlands in semiarid regions of the world are threatened by climatic change and other human impacts. In the southwestern USA, climate and culturally driven changes to the structure and fire regimes of dry coniferous forests over recent centuries are well documented by tree-ring archives. However, the roles of climate and people as drivers of millennial-scale changes are less understood. We present a new record of vegetation dynamics and regional fire activity inferred from pollen, microscopic charcoal, and sediment geochemistry from Santa Fe Lake, NM (3532 m a.s.l.), the southernmost natural lake in the Rocky Mountains. Declining elemental intensities (e.g., Ti, Fe, Si) record local deglaciation after 14,000 cal yr BP followed by upslope expansion of trees indicated by increasing <em>Pinus</em> and <em>Picea</em> pollen percentages as the climate warmed during the Late Glacial. Cool, dry growing seasons probably limited the establishment of dense forests until after 12,200 cal yr BP when we hypothesize that <em>Pinus ponderosa</em> (ponderosa pine) expanded regionally (i.e., within 10–100 km) due to continued warming and a possible increase in monsoonal precipitation. Subalpine forests established near Santa Fe Lake by 10,300 cal yr BP as indicated by abundant conifer stomates and increasing <em>Picea</em> and <em>Pinus aristata</em> pollen percentages, which are highest after 5100 cal yr BP. Increasing <em>Juniperus</em>-type, <em>Quercus</em>, and <em>Pinus edulis</em>-type pollen record changes in vegetation belts at lower elevations after 10,300 cal yr BP. Maize pollen, an unambiguous indicator of Puebloan agriculture, first appears at 800 cal yr BP (1150 cal yr CE) and is present through 1600 cal yr CE when Spanish colonization brought cultural upheaval and population loss to local indigenous communities. Regional fire activity, inferred from microscopic charcoal influx, remained relatively constant for most of our record. However, average microscopic charcoal influx more than doubled relative to the rest of the Holocene during the last 2000 years, with the highest influx after 1550 cal yr BP (400 cal yr CE). The increased influx of microscopic charcoal coincides with archaeological evidence for dramatic regional population growth in the northern Rio Grande region and probably reflects extensive cultural burning associated with the development of an agricultural economy. Although climate was an important driver of vegetation change and fire regimes in the mountains of the southwestern USA during the Holocene, our results suggest that human impacts on regional burning during the last 2000 years far exceeded earlier climate-driven variation.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"376 ","pages":"Article 109821"},"PeriodicalIF":3.3,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Tsambagarav Massif in the Mongolian Altai preserves a detailed record of glacial fluctuations from the Late Pleistocene to the present. Using geomorphological mapping, 10Be surface exposure dating, equilibrium line altitude (ELA) reconstructions, and geomorphometric analysis, we reconstruct the extent, timing, and dynamics of glacier advances across the massif. Our results indicate that the maximum glacial advance in the Ulaan Am (southwestern) Valley predated global Last Glacial Maximum (gLGM), occurring during MIS 3 (∼40 ka), with a subsequent readvance between ∼31 and 21 ka. In contrast, other glaciers, including the Tsagaan Seer (southwestern) and Yamaat (northern), reached their maximum positions broadly synchronous with the gLGM (∼26.5–19 ka). Furthermore, the Bituu Ereg (eastern) Valley records a significant Late Glacial expansion at ∼15.4 ka. Following these advances, glaciers retreated abruptly and the massif was completely deglaciated by the mid-Holocene thermal maximum. Glaciers subsequently reformed during the Neoglacial (∼6 ka) and responded sensitively to centennial-scale climate variability, including advances during the Little Ice Age (LIA) and rapid retreat under recent warming. Modern and Late Pleistocene ELAs exhibit a clear regional rise from the northwest toward the southeast across the Altai Mountains. The magnitude of Late Pleistocene ELA depressions follows the same orientation, reflecting an increased glacial sensitivity to climatic shifts in more arid environments. Throughout the massif, glacial distribution and magnitude have been consistently modulated by topographic controls rather than climate alone. Specifically, northern and eastern slopes supported the most extensive ice cover; northern glaciers were sustained by reduced solar radiation through topographic shading, while eastern glaciers were possibly driven by enhanced snow accumulation from westerly wind drift and the structural eastward tilt of the massif. These findings highlight the critical interplay between regional climate and local terrain in shaping glacial histories in arid high-mountain environments, contributing to a broader understanding of Quaternary glaciation across Central Asia.
{"title":"Glacial chronology and topographic controls in the Tsambagarav Massif, western Mongolia: Insights from 10Be dating","authors":"Purevmaa Khandsuren , Yeong Bae Seong , Hyun Hee Rhee , Otgonbayar Demberel , Byung Yong Yu","doi":"10.1016/j.quascirev.2026.109817","DOIUrl":"10.1016/j.quascirev.2026.109817","url":null,"abstract":"<div><div>The Tsambagarav Massif in the Mongolian Altai preserves a detailed record of glacial fluctuations from the Late Pleistocene to the present. Using geomorphological mapping, <sup>10</sup>Be surface exposure dating, equilibrium line altitude (ELA) reconstructions, and geomorphometric analysis, we reconstruct the extent, timing, and dynamics of glacier advances across the massif. Our results indicate that the maximum glacial advance in the Ulaan Am (southwestern) Valley predated global Last Glacial Maximum (gLGM), occurring during MIS 3 (∼40 ka), with a subsequent readvance between ∼31 and 21 ka. In contrast, other glaciers, including the Tsagaan Seer (southwestern) and Yamaat (northern), reached their maximum positions broadly synchronous with the gLGM (∼26.5–19 ka). Furthermore, the Bituu Ereg (eastern) Valley records a significant Late Glacial expansion at ∼15.4 ka. Following these advances, glaciers retreated abruptly and the massif was completely deglaciated by the mid-Holocene thermal maximum. Glaciers subsequently reformed during the Neoglacial (∼6 ka) and responded sensitively to centennial-scale climate variability, including advances during the Little Ice Age (LIA) and rapid retreat under recent warming. Modern and Late Pleistocene ELAs exhibit a clear regional rise from the northwest toward the southeast across the Altai Mountains. The magnitude of Late Pleistocene ELA depressions follows the same orientation, reflecting an increased glacial sensitivity to climatic shifts in more arid environments. Throughout the massif, glacial distribution and magnitude have been consistently modulated by topographic controls rather than climate alone. Specifically, northern and eastern slopes supported the most extensive ice cover; northern glaciers were sustained by reduced solar radiation through topographic shading, while eastern glaciers were possibly driven by enhanced snow accumulation from westerly wind drift and the structural eastward tilt of the massif. These findings highlight the critical interplay between regional climate and local terrain in shaping glacial histories in arid high-mountain environments, contributing to a broader understanding of Quaternary glaciation across Central Asia.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"376 ","pages":"Article 109817"},"PeriodicalIF":3.3,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-28DOI: 10.1016/j.quascirev.2026.109839
Pengchao Zhang , Tao Wang , Yueheng Jin , Dan Liu
Since the Industrial Revolution, global climate change has shifted from being primarily driven by natural forces to being significantly influenced by both natural forces and human activities, leading to marked climatic changes on the Tibetan Plateau. However, the responses of the plateau’s ecosystems to climate change, influenced by shifting underlying drivers, remain unclear. In this study, we examined the change characteristics, climatic drivers, and potential risks of destabilization for the Tibetan Plateau’s permafrost, forest cover, and carbon stocks from a millennial perspective (850–2020 CE), utilizing the dynamic global vegetation model, the Community Land Model version 4.5. Compared to the relative stability from pre-1850, the post-1950 period witnessed a significant change in permafrost area, forest cover, and vegetation carbon stock, with changes of −21 %, +40 %, and +14 %, respectively, compared to pre-1850 levels. Temperature and longwave radiation significantly contributed to the noticeable decline in permafrost area, while temperature, precipitation, and CO2 notably promoted vegetation growth. Moreover, permafrost had exhibited early-warning signals that it was approaching critical thresholds. Our findings underscore that the Tibetan Plateau has undergone drastic changes since 1950, with permafrost already reaching tipping points, which is crucial for enhancing the ecological security of the plateau and its surrounding regions.
{"title":"The evolution and drivers of changes in Tibetan terrestrial ecosystems over the last millennium","authors":"Pengchao Zhang , Tao Wang , Yueheng Jin , Dan Liu","doi":"10.1016/j.quascirev.2026.109839","DOIUrl":"10.1016/j.quascirev.2026.109839","url":null,"abstract":"<div><div>Since the Industrial Revolution, global climate change has shifted from being primarily driven by natural forces to being significantly influenced by both natural forces and human activities, leading to marked climatic changes on the Tibetan Plateau. However, the responses of the plateau’s ecosystems to climate change, influenced by shifting underlying drivers, remain unclear. In this study, we examined the change characteristics, climatic drivers, and potential risks of destabilization for the Tibetan Plateau’s permafrost, forest cover, and carbon stocks from a millennial perspective (850–2020 CE), utilizing the dynamic global vegetation model, the Community Land Model version 4.5. Compared to the relative stability from pre-1850, the post-1950 period witnessed a significant change in permafrost area, forest cover, and vegetation carbon stock, with changes of −21 %, +40 %, and +14 %, respectively, compared to pre-1850 levels. Temperature and longwave radiation significantly contributed to the noticeable decline in permafrost area, while temperature, precipitation, and CO<sub>2</sub> notably promoted vegetation growth. Moreover, permafrost had exhibited early-warning signals that it was approaching critical thresholds. Our findings underscore that the Tibetan Plateau has undergone drastic changes since 1950, with permafrost already reaching tipping points, which is crucial for enhancing the ecological security of the plateau and its surrounding regions.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"376 ","pages":"Article 109839"},"PeriodicalIF":3.3,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-27DOI: 10.1016/j.quascirev.2026.109816
Desmond Yeo , Yongsong Huang , Fei Guo , Richard S. Vachula , Karen J. Wang , Jonathan A. O'Donnell , Steven C. Clemens , James M. Russell
Accurate age control is a prerequisite for paleoclimate and paleoenvironmental research but remains a persistent challenge for Arctic lake sediment cores. Well-dated regional tephrochronologies can provide robust stratigraphic markers in sediments. In Arctic Eastern Beringia, the Old Crow tephra (OCt) is one of the most widely distributed late Quaternary tephras and serves as an important stratigraphic anchor beyond the radiocarbon range (>50 ka BP). However, the age of the OCt remains debated and has undergone numerous revisions, with studies using different dating methodologies to ascribe ages ranging from 124 ka to 203 ka. While the commonly reported age of the OCt based on fission track dating is 124 ± 10 ka, a recent study using uranium-thorium/helium ((U-Th)/He) dating of zircon placed the OCt at 202.9 ± 9.5 ka. Here, we independently find an age of 179.0 ± 4.6 ka for the OCt from a lacustrine sediment record in Alaska (Imuruk Lake) with confirmation using the marine benthic δ18O chronology. This revises the current tephrostratigraphic framework in this region. We also report a previously undocumented mafic tephra layer (IM#1), which is likely a local eruption on the Seward Peninsula, with an age of 157.2 ± 4.7 ka, providing a new tephrostratigraphic marker for this region.
准确的年龄控制是古气候和古环境研究的先决条件，也是北极湖泊沉积物岩心研究的长期挑战。年代确定的区域地层年代学可以为沉积物提供可靠的地层标志。在北极东白令陆桥，老克罗热层（OCt）是晚第四纪分布最广泛的热层之一，是放射性碳范围（>50 ka BP）以外重要的地层锚点。然而，OCt的年龄仍然存在争议，并经历了多次修订，研究使用不同的测年方法将年龄从124 ka到203 ka不等。虽然基于裂变径迹测年的OCt年龄通常报道为124±10 ka，但最近一项使用锆石铀-钍/氦（(U-Th)/He）测年的研究将OCt定在202.9±9.5 ka。在此，我们独立地从阿拉斯加（Imuruk湖）的湖泊沉积记录中发现OCt的年龄为179.0±4.6 ka，并使用海洋底栖生物δ18O年代学进行了确认。这改变了该地区目前的地层格架。此外，我们还报道了在西沃德半岛发现的基性温层（im# 1），其年龄为157.2±4.7 ka，为该地区提供了新的温层地层标志。
{"title":"New evidence for a 179 ka age of the Old Crow tephra","authors":"Desmond Yeo , Yongsong Huang , Fei Guo , Richard S. Vachula , Karen J. Wang , Jonathan A. O'Donnell , Steven C. Clemens , James M. Russell","doi":"10.1016/j.quascirev.2026.109816","DOIUrl":"10.1016/j.quascirev.2026.109816","url":null,"abstract":"<div><div>Accurate age control is a prerequisite for paleoclimate and paleoenvironmental research but remains a persistent challenge for Arctic lake sediment cores. Well-dated regional tephrochronologies can provide robust stratigraphic markers in sediments. In Arctic Eastern Beringia, the Old Crow tephra (OCt) is one of the most widely distributed late Quaternary tephras and serves as an important stratigraphic anchor beyond the radiocarbon range (>50 ka BP). However, the age of the OCt remains debated and has undergone numerous revisions, with studies using different dating methodologies to ascribe ages ranging from 124 ka to 203 ka. While the commonly reported age of the OCt based on fission track dating is 124 ± 10 ka, a recent study using uranium-thorium/helium ((U-Th)/He) dating of zircon placed the OCt at 202.9 ± 9.5 ka. Here, we independently find an age of 179.0 ± 4.6 ka for the OCt from a lacustrine sediment record in Alaska (Imuruk Lake) with confirmation using the marine benthic δ<sup>18</sup>O chronology. This revises the current tephrostratigraphic framework in this region. We also report a previously undocumented mafic tephra layer (IM#1), which is likely a local eruption on the Seward Peninsula, with an age of 157.2 ± 4.7 ka, providing a new tephrostratigraphic marker for this region.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"376 ","pages":"Article 109816"},"PeriodicalIF":3.3,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080570","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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