Quaternary Science Reviews最新文献

{"title":"The Holocene precipitation dipole pattern in the Asian drylands: Mechanisms and processes from PMIP4 simulations and paleo-proxy evidence","authors":"Shuai Ma ,&nbsp;Shengqian Chen ,&nbsp;Jianhui Chen ,&nbsp;Jie Chen ,&nbsp;Dianbin Cao ,&nbsp;Elena Xoplaki ,&nbsp;Jürg Luterbacher ,&nbsp;Fahu Chen ,&nbsp;Wei Huang","doi":"10.1016/j.quascirev.2024.109091","DOIUrl":"10.1016/j.quascirev.2024.109091","url":null,"abstract":"<div><div>Asian drylands encompass Arid Central Asia (ACA) and West Asia (WA), where water vapor transport is consistently governed by the westerlies. Recent research has identified a dipole pattern in Holocene hydroclimate changes between the ACA and WA, challenging previous assumptions of uniform hydroclimate shifts across the westerlies-dominated mid-latitudes of the Northern Hemisphere. However, the mechanisms behind the dipole pattern remain largely unknown. Our findings demonstrate that PMIP4 models accurately reproduced the dipole pattern, attributing it mainly to contrasting spring precipitation changes. From the middle to late Holocene, strengthened westerlies led to increased precipitation in the ACA. In contrast, rising spring solar insolation intensified the subtropical high, leading to reduced water vapor and increased descending air movement in WA, which decreased precipitation in the region. Our study suggests that WA is a distinctive region within the westerlies-dominated mid-latitudes, where low-latitude processes led to inconsistent precipitation variations from the middle to late Holocene.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"347 ","pages":"Article 109091"},"PeriodicalIF":3.2,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722385","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}

{"title":"Radiocarbon age-offset measurements reveal shifts in the transport mechanism and age of permafrost-derived organic carbon from Burial Lake, arctic Alaska from MIS 3 to present","authors":"Hailey Sinon ,&nbsp;Mark Abbott ,&nbsp;Eitan Shelef ,&nbsp;Brad Rosenheim ,&nbsp;Devon Firesinger ,&nbsp;Melissa Griffore ,&nbsp;Matt Finkenbinder ,&nbsp;Bruce Finney ,&nbsp;Mary Edwards","doi":"10.1016/j.quascirev.2024.109083","DOIUrl":"10.1016/j.quascirev.2024.109083","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The stability of arctic permafrost and the carbon it contains are currently threatened by a rapidly warming climate. Burial Lake, situated in northwestern arctic Alaska, is underlain by continuous permafrost and has a uniquely rich set of paleoclimate proxy data that comprise a 40-ka record of climate and environmental change extending well into Marine Isotope Stage (MIS) 3. Here, we examine the relationship between erosion, subsurface hydrology, and primary productivity from the Burial Lake sediments to improve our understanding of the links between climate, hydrology, sediment transport, and carbon mobility. The record is developed with radiocarbon (&lt;sup&gt;14&lt;/sup&gt;C) age-offsets from two independent methods used to date the lake sediments: 1) &lt;sup&gt;14&lt;/sup&gt;C measurements on paired bulk sediment and plant macrofossils from the same stratigraphic layer of lake sediment and 2) ramped pyrolysis-oxidation (RPO) &lt;sup&gt;14&lt;/sup&gt;C analysis that separates fractions of organic carbon (OC) from a single bulk sediment sample based on thermochemical differences through continuous heating. As lakes capture and archive OC transported from the watershed, changes in the amount and relative age of permafrost-derived OC mobilized during past climatic variations can be documented by examining how age-offsets change over time. The Burial Lake sediment revealed higher age-offsets during the cold Last Glacial Maximum (LGM; ∼29-17 ka) than the comparatively warmer post-glacial (∼17 ka-present) and the MIS 3 interstadial (∼40-29 ka) periods. The relatively warm, wet climate of the post-glacial period promoted both terrestrial and aquatic productivity, resulting in increased OC deposition, and it likely favored transport via subsurface flow of dissolved OC (DOC) sourced from soils. This resulted in a greater flux of contemporary OC relative to ancient OC into the lake sediment, lowering the average age offset to ∼2 ka. In contrast, the low-productivity conditions of the LGM resulted in slow soil accumulation rates, leaving ancient OC in a shallower position in the soil profile and allowing it to be easily eroded in the form of particulate OC (POC). Although the amount of total OC deposited in the lakebed during the LGM is small relative to post-glacial deposition, the majority is ancient, which leads to a relatively high average age offset of ∼9 ka. Finally, climate and environmental conditions of the MIS 3 interstadial were intermediate between those of the post-glacial and the LGM. As with post-glacial sediments, a relatively large amount of OC is present; however, the vast majority of it is ancient (more similar to the LGM), and it produces an average age offset of ∼6 ka. The Burial Lake radiocarbon record demonstrates the complexities of the thaw and mobilization of permafrost OC in arctic Alaska, including the balance between production, transport, deposition, remobilization, and preservation. This record highlights the importance of considering factors that b","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"347 ","pages":"Article 109083"},"PeriodicalIF":3.2,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142721723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geomagnetic field modulation of cosmogenic 129I recorded in Chinese loess sequences","authors":"Yukun Fan ,&nbsp;Jibao Dong ,&nbsp;Zhongyi Liu ,&nbsp;Xue Zhao ,&nbsp;Yanyun Wang ,&nbsp;Xianghui Kong ,&nbsp;Qi Liu ,&nbsp;Weijian Zhou ,&nbsp;Xiaolin Hou","doi":"10.1016/j.quascirev.2024.109094","DOIUrl":"10.1016/j.quascirev.2024.109094","url":null,"abstract":"<div><div>The larger dispersion of pre-nuclear Iodine-129/Iodine-127 (¹²⁹I/¹²⁷I) in terrestrial sediments and the complexity of environmental factors made terrestrial ¹²⁹I dating extremely difficult. Sorting and dissociating possible influences will hopefully lead to a pattern of change in the pre-nuclear ¹²⁹I/¹²⁷I and accordingly an initial value for terrestrial dating. Here, we present the iodine isotope records of two loess-paleosol sections from Chinese Loess Plateau. The coupled variations of the ¹²⁹I fluxes and other paleomagnetic field records, with known paleomagnetic excursions being clearly matched, indicated the prominent modulation of cosmogenic ¹²⁹I production rate by paleomagnetic field, while the variation of ¹²⁷I concentrations again verified the climate control. Discrepancies in amplitudes of ¹²⁹I fluxes and other paleomagnetic field records were supposed to be a result of possible climate impact and organic matter degradation. These findings add new information to our knowledge of iodine-isotope composition, and are instructive for future study methodology.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"347 ","pages":"Article 109094"},"PeriodicalIF":3.2,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142721724","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}

{"title":"Testing assumptions of spheroidal carbonaceous particle (SCP) quantification at very low concentrations: Implications for dating geologic archives","authors":"Emma D. Henderson,&nbsp;Ann S. Ojeda,&nbsp;Richard S. Vachula","doi":"10.1016/j.quascirev.2024.109092","DOIUrl":"10.1016/j.quascirev.2024.109092","url":null,"abstract":"<div><div>Spheroidal carbonaceous particles (SCPs) are preserved in geologic archives such as lake sediments, ice cores, or peatlands, and can provide chronology for cores. SCPs are only produced during the combustion of coal and fuel oil, so they are a reliable global marker of the onset of industrialization and can be used to track deposition from these sources. While the usage of SCPs as chronostratigraphic indicators in recent sediments is common, the enumerative method of quantifying their sedimentary concentrations has remained virtually unchanged, and assumes that one subsample is representative of the entire sediment sample. We test this assumption and explore its implications for the SCP chronological method of dating recent sediments by analyzing multiple subsamples to characterize the precision and accuracy of SCP concentration measurements. Notably, we do not use the conventional SCP quantification method and focus on samples with lower concentrations and larger SCPs than are typically quantified in the literature. However, we base our conclusions and inferences on insights gained from analyses of the effects of subsampling on SCP numerosity (counts), which are translatable insights to all sizes and methods of SCPs quantification which rely on particle counts. We quantified SCPs in sets of 30 subsamples for 14 riverine sites (n = 420). SCP concentrations varied (0 SCPs/gDM – 2141±825 SCPs/gDM), but reflect the typical ranges of SCP concentrations quantified in modern sediments in other environmental settings. For each site, we used a bootstrapping method to approximate the theoretical mean of SCPs at 1–30 subsample sizes, then compared the theoretical mean and relative standard deviation. We found that enumerating 10 subsamples per sample better represents the theoretical mean of SCPs than the enumeration of 1 subsample, especially for lower SCP concentration samples. The greatest chance for falsely reporting the absence of SCPs was when &lt;10 SCPs/gDM were measured in fewer than 10 subsamples, indicating that more replicates could provide greater confidence in SCP-based dating of geologic archives. If aiming to delineate the stratigraphic onset of SCP presence for dating purposes, we recommend enumerating a minimum of 10 subsamples for samples with low SCP concentrations to ensure the reliability of these measurements. We acknowledge that enumerating multiple subsamples is time and resource intensive, but provide some strategies (e.g., limiting subsampling) for minimizing additional cost and argue that the advantages afforded for dating reliability outweigh the costs in paleoenvironmental research.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"347 ","pages":"Article 109092"},"PeriodicalIF":3.2,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722384","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}

{"title":"Northern hemisphere mid-latitudes as a key region for reconciling the Holocene temperature conundrum","authors":"Yukun Zheng ,&nbsp;Zhengyu Liu ,&nbsp;Weipeng Zheng ,&nbsp;Hongyan Liu","doi":"10.1016/j.quascirev.2024.109090","DOIUrl":"10.1016/j.quascirev.2024.109090","url":null,"abstract":"<div><div>The classical Holocene temperature reconstruction indicates a cooling trend following the mid-Holocene thermal maximum. However, significant discrepancies exist between the temperature changes predicted by climate models and those derived from proxy data. Proxy sites are predominantly concentrated in the Northern Hemisphere mid-latitudes, where temperature variations align closely with global climate trends. Notably, in the Northern Hemisphere mid-latitudes, the differences between climate model simulations and proxy data are most pronounced. As such, the Northern Hemisphere mid-latitudes represent a crucial region for reconciling Holocene climate dynamics and addressing the Holocene temperature conundrum. Through an analysis of the latitudinal variation in solar radiation and its impact on temperature, this study underscores the pivotal role of this region in temperature reconstructions, particularly in resolving the ongoing discrepancies in Holocene temperature trends.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"347 ","pages":"Article 109090"},"PeriodicalIF":3.2,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142721729","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}

{"title":"26Al/10Be burial dating of Majuangou sites in Nihewan Basin, northern China","authors":"Hua Tu ,&nbsp;Xinfeng Zhang ,&nbsp;Lan Luo ,&nbsp;Fei Xie ,&nbsp;Fei Han ,&nbsp;Zhongping Lai ,&nbsp;Darryl E. Granger ,&nbsp;Guanjun Shen","doi":"10.1016/j.quascirev.2024.109086","DOIUrl":"10.1016/j.quascirev.2024.109086","url":null,"abstract":"<div><div>The Paleolithic site of Majuangou-III (MJG-III) in the Nihewan Basin, magnetostratigraphically dated to 1.66 million years ago (Ma), has been widely cited as documenting one of the earliest human settlements in China. Nevertheless, it remains important to cross-check the paleomagnetic dating with an independent and well-established radio-isotopic dating method. Here we report the application of ²⁶Al/¹⁰Be burial dating to the Majuangou sites, assigning 1.28 ± 0.11 Ma (1σ), &gt;1.49 Ma and close to 1.63 ± 0.09 Ma to Banshan, MJG-I and MJG-III, respectively. The proposed age sequence is supported by the general consistency between dates and stratigraphy as well as the consistency of dates between the samples from excavated cross-sections and those from deeply buried sediment cores. The age results agree with the previous magnetostratigraphy, providing the first radio-isotopic age for the earliest human occupation in high-latitude northern China.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"346 ","pages":"Article 109086"},"PeriodicalIF":3.2,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142697549","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}

{"title":"Reconstructing Holocene hydroclimate variability and coastal dynamics of the Nile Delta: A diatom perspective","authors":"Yanna Wang ,&nbsp;Jinqing Zhou ,&nbsp;Xiaoshuang Zhao ,&nbsp;David Kaniewski ,&nbsp;Nick Marriner ,&nbsp;Alaa Salem ,&nbsp;Jing Chen ,&nbsp;Zhongyuan Chen","doi":"10.1016/j.quascirev.2024.109070","DOIUrl":"10.1016/j.quascirev.2024.109070","url":null,"abstract":"<div><div>This study analyses diatom assemblages from a Nile Delta core (B-1) to probe Holocene hydroclimate changesand their influence on the ecological habitats of the delta coast, with a further focus on the effects of relative sea-level rise. We found that the freshwater diatom <em>Aulacoseira granulata</em> varied in tandem with hydroclimate pulses in the Nile watershed, driven by the shift of the Intertropical Convergence Zone (ITCZ), therefore serving as a proxy for palaeo-Nile flow. Based on the ecological affinities of diatom taxa, we defined 5 diatom assemblages (I-V). Assemblage I (&gt;10.0-8.5 ka BP) shows high <em>A. granulata</em> abundance (60–80%), implying peak Nile flow during the African Humid Period (AHP), at least 3 times greater than that of the recent past. Assemblage II (8.5-7.5 ka BP) sees decreased <em>A. granulata</em> (20–40%) and emergence of freshwater diatoms with benthic-oligotrophic characteristics (e.g. <em>Epithemia gibba</em>), suggesting reduced Nile flow and a delta estuary where the habitat became shallower with lower nutrient content. Assemblage III (7.5-6.0 ka BP) shows <em>A. granulata</em> resurgence (50–80%), reflecting Nile hydroclimate variability post-AHP due to the migration of the Intertropical Convergence Zone (ITCZ). The high-resolution- diatom spectra of B-1 also revealed major habitat changes, from saline to fluvial-dominated environments, around 6.0 ka BP. Assemblage IV (6.0-3.2 ka BP) indicates a notable Nile flow decline and freshwater community proliferation, coinciding with coastal habitat expansion and delta progradation due to RSL stablisation and basin-wide aridification. Assemblage V (3.2-2.0 ka BP) is marked by drought-tolerant diatoms (<em>Nitzchia amphibia, Hantzschia amphioxys</em> and <em>Cavinula cocconeiformis</em>), indicating intensified aridification.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"346 ","pages":"Article 109070"},"PeriodicalIF":3.2,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142697543","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}

{"title":"High-precision 40Ar/39Ar dating of Australasian tektites associated with bifacial tools in the Bose Basin (Xiaomei and Fengshudao sites), South China and in Vietnam (Go Da and Roc Tung 1 sites)","authors":"Véronique Michel ,&nbsp;Fred Jourdan ,&nbsp;Marie-Hélène Moncel ,&nbsp;Bernard Gratuze ,&nbsp;Guanjun Shen ,&nbsp;Wei Wang ,&nbsp;Celia Mayers ,&nbsp;Adam Frew ,&nbsp;Dominique Cauche ,&nbsp;Patricia Valensi ,&nbsp;Sylvain Gallet ,&nbsp;Anatoly P. Derevianko ,&nbsp;Alexander V. Kandyba ,&nbsp;Sergey A. Gladyshev ,&nbsp;Henry de Lumley","doi":"10.1016/j.quascirev.2024.109065","DOIUrl":"10.1016/j.quascirev.2024.109065","url":null,"abstract":"<div><div>Bifacial tools discovered at about a hundred Lower Palaeolithic sites in the Bose Basin, southern China, have been previously dated to around 800,000 years ago. This age was obtained by dating four tektites directly associated with the tools at the Nalai site using the ⁴⁰Ar/³⁹Ar method (Michel et al., 2021). Similar ages on tektites from the Bogu and Yangwu sites had been previously published, albeit with limited analytical details, by Hou et al. (2000). In this study, a total of eight tektites, discovered alongside abundant lithic artefacts including bifacial tools, were dated with the ⁴⁰Ar/³⁹Ar technique, using an incremental temperature increase approach. Six of these tektites are from two Lower Palaeolithic sites in the Bose Basin; three from Xiaomei and three others from Fengshudao (China). The remaining two tektites come from two sites in Vietnam, one from Go Da and the other from Roc-Tung 1. With the exception of the site of Go Da, the tektites were buried in lateritic sediments associated with the stone tools. At the Go Da site, the tektites were found in a layer overlying the deposit containing bifacial tools. The tektites display no signs of fluvial abrasion or reworking, making them potentially strong chronological markers. Chemical analyses of major elements and rare earth elements indicate that the tektites belong to the Australasian tektite group. This is further confirmed by new ⁴⁰Ar/³⁹Ar analyses with a weighted mean age of 787.2 ± 8.2 ka (2σ) (MSWD = 0.96, P = 0.45). Therefore, when combined with the available results on Australasian tektites, this suggests a highly precise age of 788.0 ± 2.6 ka (2σ; P = 0.84) for these tektites and consequently, for the bifacial tools in this part of Southeast Asia, located east of the Movius Line. The presence of bifacial tools attests to either a diffusion of the Acheulean from Africa or a local emergence from previous occupations and traditions in Asia.</div></div>","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"346 ","pages":"Article 109065"},"PeriodicalIF":3.2,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142697541","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}

{"title":"Modern land use changes drive shifts in nutrient cycling and diatom assemblages in the Baltic Sea coastal zone: A millennial perspective with a case study from Gamlebyviken, Swedish east coast","authors":"Elinor Andrén ,&nbsp;Olena Vinogradova ,&nbsp;Mikael Lönn ,&nbsp;Simon Belle ,&nbsp;Martin Dahl ,&nbsp;Veronica Palm ,&nbsp;Christos Katrantsiotis ,&nbsp;Anne Birgitte Nielsen ,&nbsp;Martin Jakobsson ,&nbsp;Johan Rönnby ,&nbsp;Thomas Andrén","doi":"10.1016/j.quascirev.2024.109058","DOIUrl":"10.1016/j.quascirev.2024.109058","url":null,"abstract":"&lt;div&gt;&lt;div&gt;This study aims to investigate and disentangle the impact of land use and climate variability on the Baltic Sea coastal zone from a millennial perspective. To assess the environmental status of the coastal zone we make use of siliceous microfossils (mainly diatoms), stable nitrogen and carbon isotopes, organic carbon accumulation rates, and lithological changes analyzed in a sediment core collected in Gamlebyviken, Swedish east coast, dated to cover the last 3000 years. Changes in land use and vegetation cover are modelled using pollen stratigraphical data to obtain the percentage coverage of coniferous woodland (&lt;em&gt;Pinus&lt;/em&gt; and &lt;em&gt;Picea&lt;/em&gt;), deciduous woodland, wetland (Cyperaceae), grassland (including &lt;em&gt;Juniperus&lt;/em&gt;) and cropland (cereals) while changes in climatic conditions are assessed through well-documented climatic periods that have occurred in the Baltic Sea region.&lt;/div&gt;&lt;div&gt;The reconstructed regional vegetation cover shows that already 3000 years ago, humans used the landscape for both animal husbandry (grasslands) and farming (cropland), but the impact on the Baltic coastal waters was minor. The diatom accumulation rates were quite high (∼3100–2600 cal yr BP) containing taxa indicative of high nutrient conditions/upwelling, and stable carbon isotopes show that the carbon was produced in the basin but did not result in elevated organic carbon accumulation rates. A gradual change to less marine conditions in Gamlebyviken from about 2500 to 1400 cal yr BP can be attributed to the ongoing land uplift which resulted in a more enclosed embayment with only a narrow inlet area today.&lt;/div&gt;&lt;div&gt;The Medieval Climate Anomaly (1000–700 cal yr BP/950–1250 CE) is a time where extensive eutrophication is registered in the open Baltic Sea, but afforestation is recorded between 1000 and 500 cal yr BP and attributed to the expansion of spruce favored by land-use reorganization with a transition from a one-course rotation system to the three-course rotation system fully established in southern Sweden in the 13th century, and only minor environmental change is recorded in the coastal zone.&lt;/div&gt;&lt;div&gt;The Little Ice Age is documented in our data between 400 and 250 cal yr BP/1550–1700 CE as a decrease in regional cropland (cereals) cover, possibly indicating years of poor crop harvest, and changes in the Baltic coastal zone are evidenced as low carbon and diatom accumulation rates, increase in benthic diatom taxa (low turbidity), and high abundance in diatom taxa associated with sea ice indicating a cold climate.&lt;/div&gt;&lt;div&gt;The most significant changes occurred from about 100 cal yr BP/1850 CE up to present, with a maximum regional cover of grassland and cropland (ca. 35%) at the expense of deciduous woodland, and major changes indicative of a highly eutrophic environment recorded in the coastal zone. Organic carbon accumulation rates peaked in 1968 CE at approximately 134 g C m&lt;sup&gt;2&lt;/sup&gt; yr&lt;sup&gt;−1&lt;/sup&gt; before subsequently declining ","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"346 ","pages":"Article 109058"},"PeriodicalIF":3.2,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142697542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Response to comments by Shane et al. (2024) on Hopkins, J.L., McIntosh, P.D., Vink, J., Slee, A. and Moss, P., 2024. First detection in Australia of cryptotephra likely to be derived from the 25.6 ka Ōruanui supereruption in New Zealand. Quaternary Science Reviews, 341 DOI: 10.1016/j.quascirev.2024.108856","authors":"J.L. Hopkins ,&nbsp;P.D. McIntosh ,&nbsp;J. Vink ,&nbsp;A. Slee ,&nbsp;P. Moss","doi":"10.1016/j.quascirev.2024.109052","DOIUrl":"10.1016/j.quascirev.2024.109052","url":null,"abstract":"","PeriodicalId":20926,"journal":{"name":"Quaternary Science Reviews","volume":"346 ","pages":"Article 109052"},"PeriodicalIF":3.2,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747850","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}