Palaeogeography, Palaeoclimatology, Palaeoecology最新文献

{"title":"Quantitative climate reconstruction of the Mid- to late Holocene based on pollen records from Northern Shandong, China","authors":"Yaping Li ,&nbsp;Wenhao Zheng ,&nbsp;Wenfei Liu ,&nbsp;Kai Su ,&nbsp;Wei Liu ,&nbsp;Junna Zhang ,&nbsp;Kai Ning ,&nbsp;Zhenjing Yang ,&nbsp;Guiyun Jin","doi":"10.1016/j.palaeo.2025.112815","DOIUrl":"10.1016/j.palaeo.2025.112815","url":null,"abstract":"<div><div>Pollen serves as a critical proxy for quantitative paleoclimatic reconstruction, with high-quality modern pollen databases and advanced modeling approaches significantly enhancing the reliability of reconstructed climatic parameters and providing multifaceted insights into past climate dynamics. This study presents a quantitative paleoclimatic reconstruction based on pollen analysis from the Dingjiazhuang profile in northern Shandong, China. The LWWA (inverse) model at 900 km was identified as the optimal model for climatic parameter reconstruction. Our results delineate periodic changes of Mid- to Late Holocene climate in the study area through reconstructed curves of annual precipitation (Pann), mean precipitation of the warmest month (MPwa), mean temperature of the warmest month (MTwa), and mean temperature of the coldest month (MTco) spanning 8–2.6 ka. Five distinct climatic phases were identified: A cool-dry fluctuation phase (8.1–6.8 ka), a warm-humid Mid-Holocene Climatic Optimum (6.8–6.2 ka), a transitional cool-humid phase (6.2–5.3 ka), a warm-dry phase (5.3–3.1 ka), and a cool-dry phase (3.1–2.6 ka). Millennial-scale variations were predominantly driven by the interplay between the East Asian Summer Monsoon (EASM) and East Asian Winter Monsoon (EAWM). Centennial-scale anomalies include 8.2 ka, 5.5 ka, and 4.2 ka events. The complex forcing mechanisms underlying these events warrant further investigation. This study represents the first attempt to establish climate quantification in northern Shandong, providing critical data support for understanding the environmental evolution of the East Asian monsoon region during the Holocene.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"665 ","pages":"Article 112815"},"PeriodicalIF":2.6,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143454872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tectonic setting, paleoenvironment and REE source of the Lower Cambrian phosphorites, Yangtze Block (South China)","authors":"Chuan Guo ,&nbsp;Yong Fu ,&nbsp;Peng Xia ,&nbsp;Zhen Yang ,&nbsp;Yanjun Li ,&nbsp;Zhongfei Pan","doi":"10.1016/j.palaeo.2025.112821","DOIUrl":"10.1016/j.palaeo.2025.112821","url":null,"abstract":"<div><div>The phosphorites of the Lower Cambrian Gezhongwu Formation on the Yangtze Block of South China (specially Zhijin area of Guizhou province) yield exceptionally high rare earth elements (REE) contents up to 1700 ppm, which could serve a potential source of REE industry. The tectonic setting and paleoenvironment of the REE enrichment of the Gezhongwu phosphorites and the REE source in these phosphorites, however, remain poorly constrained. This study conducts a comprehensive analysis of lithology and bulk-rock major and trace elements (including REE) on the Ediacaran-Cambrian (<em>E</em>-C) successions of three sections (Gezhongwu, Zhalagou and Jiebeidong) in different depositional settings of the upper-middle Yangtze areas, in order to elucidate the tectonic setting, paleoenvironment and the REE source of the Gezhongwu phosphorites in the Zhijin area of Guizhou province. The Post-Archean Australian Shale (PAAS, subscript N)-normalized REE patterns of the <em>E</em>-C intervals in the study area exhibit seawater-like signatures (e.g., minor LREE depletion, HREE enrichment and positive La anomalies). In addition, the <em>E</em>-C successions in certain sections share positive Eu anomalies ([Eu/Eu*]_N) of varying degrees (e.g., Zhalagou) and relatively low Y/Ho ratios (average 30; Zhalagou and Jiebeidong sections), suggesting the variable contributions of high-temperature hydrothermal fluids during the <em>E</em>-C period. Additionally, the negative Ce anomalies ([Ce/Ce*]_N) with a wide range (0.32–0.87) of the E-C strata and the reported redox fluctuations in the South China indicate fluctuating oxygenation conditions across different depositional settings and high redox heterogeneity. The lack of correlation between total REE contents (ƩREE) and Zr and Th of the Gezhongwu phosphorites in the Zhijin area implies a minimal contribution of terrestrial sources. Considering the tectonic setting and the REE profiles of the Gezhongwu phosphorites in the Zhijin area, it is hypothesized that a mixture of seawater and varying amounts (0.1 % ∼ 1 %) of high-temperature hydrothermal fluids is likely the primary source for the REE enrichment of the Gezhongwu phosphorites, and high-temperature hydrothermal fluids might contribute a significant, yet potentially underestimated, quantities of REE. This study offers valuable insights into understanding the tectonic setting and paleoenvironment of REE enrichment in phosphorites and their sources in the geological records.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"665 ","pages":"Article 112821"},"PeriodicalIF":2.6,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143445453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 for presence of alternative photosynthetic pathways in plants during the Mississippian","authors":"Tara A. Putri ,&nbsp;Benjamin C. Gill ,&nbsp;Stephen E. Scheckler ,&nbsp;Rachel Reid","doi":"10.1016/j.palaeo.2025.112819","DOIUrl":"10.1016/j.palaeo.2025.112819","url":null,"abstract":"<div><div>The evolutionary emergence of the CAM (Crassulacean Acid Metabolism) photosynthetic pathway is unknown, but some studies have speculated it may have emerged during the Devonian-Carboniferous when vascular plants first proliferated in terrestrial environments. Specifically, some Carboniferous arborescent lycopsids (e.g., <em>Lepidodendropsis</em>) have morphological features similar to modern CAM plants. In this study, we systematically examine the carbon isotope compositions of an assemblage of Tournaisian (Mississippian) <em>Lepidodendropsis</em> for evidence of alternative photosynthetic pathways. Previous work suggests that the CAM pathway can produce δ¹³C signatures that are distinct from the C₃ pathway due to differences in isotopic discrimination during carbon fixation. Analyses were performed on <em>Lepidodendropsis</em> sp. and coeval presumed C₃ plants (i.e. <em>Genselia and Rhodeopteridium</em> sp.) from the same fossil plant assemblage within the Price Formation of southwestern Virginia, U.S.A<em>.</em> The investigated plant fossils were limited to single assemblages from four localities within the Price Formation in an attempt to control differences in environmental conditions (differences in CO₂, local climate, etc.) and diagenetic history that could affect the carbon isotope compositions of the fossil plants. The full dataset yielded a mean δ¹³C of −22.5 ± 0.7 ‰ for the CAM/CAM-like plants (<em>n</em> = 35) and a mean δ¹³C of −22.7 ± 0.7 ‰ for the suggested C₃ plants (<em>n</em> = 36). The lack of isotopic difference between the coeval C₃ plants and that of <em>Lepidodendropsis</em> does not preclude the possibility that these plants were using a CAM pathway and leaves open three possibilities for the photosynthetic pathway that <em>Lepidodendropsis</em> employed: 1) the C₃ metabolism 2) aquatic CAM or 3) facultative CAM. More broadly, our study provides a more systematic framework for future studies to test for the presence of a CAM or CAM-like pathway in ancient plants.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"665 ","pages":"Article 112819"},"PeriodicalIF":2.6,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143454200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Migrating incision wave and the bottom-up drainage integration of the upper Yangtze River on the Tibetan Plateau before Pliocene times","authors":"Yang Yu,&nbsp;Xianyan Wang,&nbsp;Zhengchen Li,&nbsp;Qiang Su,&nbsp;Dongxu Cai,&nbsp;Haohan Wu,&nbsp;Huayu Lu","doi":"10.1016/j.palaeo.2025.112810","DOIUrl":"10.1016/j.palaeo.2025.112810","url":null,"abstract":"<div><div>The evolution of the upper Yangtze River (UYR) is intricately tied to the developing topography shaped by the uplift of the southeastern Tibetan Plateau and the evolution of the Asian Monsoon. Diverse processes governing drainage evolution have given rise to varying perspectives on the formation age of the UYR. This study undertakes a comprehensive analysis, based on linear river-profile inversions of 43 catchments draining into the UYR, to reconstruct the spatial and temporal patterns of fluvial incision history as chronicled by river knickpoint migration. The results reveal that the initiation epochs of knickpoints migration in tributaries span from 10 Ma to 3 Ma, and exhibit a decreasing trend as one moves upstream along the main channel. The main knickpoint in the trunk, a consequence of intensified uplift in the southeastern Tibetan Plateau during the middle Miocene, migrated headward via a bottom-up integration process at a calculated rate of 118–274 km/Myr. This migratory knickpoint and headward erosion in the drainage played a pivotal role in integrating watersheds and expanding the UYR's influence onto the inner Tibetan Plateau, a process that was largely complete prior to the start of the Pliocene.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"665 ","pages":"Article 112810"},"PeriodicalIF":2.6,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143436676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Darriwilian radiolarians from slope facies sediments, Ordos Basin, North China and their paleoecological and paleogeographical implications","authors":"Xue-Jin Wu ,&nbsp;Jia-Qi Song ,&nbsp;Hui Luo ,&nbsp;Yang Liu ,&nbsp;Jonathan C. Aitchison ,&nbsp;Yu-Jing Wang ,&nbsp;Kui Yan ,&nbsp;Zhong-Yang Chen ,&nbsp;Di Chen ,&nbsp;Yuan-Dong Zhang","doi":"10.1016/j.palaeo.2025.112818","DOIUrl":"10.1016/j.palaeo.2025.112818","url":null,"abstract":"<div><div>A well-preserved Darriwilian radiolarian assemblage is reported from the Ordos Basin, North China. This new assemblage, recovered from the Kelimoli Formation in the Xilaifeng section, Wuhai area, Inner Mongolia, contains five species of five genera, including one new species. They are <em>Proventocitum procerulum</em> Nazarov, <em>Oriundogutta bella</em> Wang, <em>Inanigutta complanata</em> (Nazarov), <em>Spongentactinia armillata</em> (Nazarov), and <em>Nyfrieslandia kelimoli</em> sp. nov. The new species predominates this assemblage. Furthermore, the radiolarian assemblage from the lime mudstone of the Kelimoli Formation was associated with some other kinds of fossils including conodonts, brachiopods and acritarchs, which indicates a slope facies of the formation. The geographic distribution of Darriwilian radiolarian occurrences in Laurentia and peri-Gondwana region, based on available global data, highlights a preference of radiolarians for areas at low paleo-latitude. The results of quantitative biogeographic analyses, including Network Analysis (NA), Cluster Analysis (CA) and Non-metric Multidimensional Scaling (NMDS), indicate notable biogeographic provincialism of Darriwilian radiolarians in low-latitude areas (both in the southern and northern hemispheres). The southern hemisphere assemblages differ from those of the north in having higher taxonomic diversity, which may have been associated with oceanic circulation.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"665 ","pages":"Article 112818"},"PeriodicalIF":2.6,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143454870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineralogy of the Yangtze (Changjiang) shoal: Implications for provenance and land–sea interaction response to sea level changes since MIS 6","authors":"Junqiang Zhang ,&nbsp;Jian Liu ,&nbsp;Xin Zhang ,&nbsp;Baojing Yue ,&nbsp;Jiandong Qiu","doi":"10.1016/j.palaeo.2025.112813","DOIUrl":"10.1016/j.palaeo.2025.112813","url":null,"abstract":"<div><div>In this study, high–resolution detrital mineral analysis was conducted on sediments from a 70.20 m borehole (core CRE–1402) located on the Yangtze (Changjiang) Shoal, which is one of the largest sheets–like sand banks globally. The research aims to offer detailed insights into the provenance of the Yangtze Shoal, as well as the corresponding sedimentary processes linked to its formation. The findings reveal that the light mineral assemblages are primarily composed of plagioclase, lithics fragments, and quartz, while the heavy mineral assemblages are dominated by epidote, hornblende, and carbonate, followed by weathered mica, biotite, actinolite–tremolit, and ilmenite. The entire suite of detrital minerals of core CRE–1402 sediments closely resemble to the lower reaches of the Yangtze River and offshore areas of Yangtze River delta. The hornblende to epidote ratios (H/E) and garnet to epidote ratios (G/E) exhibit stable values throughout the core, indicating that the sediments in core CRE–1402 primarily originated from a single terrigenous source. The Quartz–Feldspar–Lithics (QFL) ternary plot of core CRE–1402 aligns closely to the ancient Yangtze River and the subaqueous Yangtze River delta, yet far from the subaqueous Yellow River delta. Core CRE–1402 sediments were derived from Yangtze River. The Yangtze River flowed through the study area during the low sea level period of Marine Isotope Stage (MIS) 6, and to other areas from MIS 5 to MIS 2. As sea level rose during early MIS 1, the river channel incised, and the estuary shifted southward along with the formation of coastal currents. During high sea levels, the Yangtze River estuary migrated south of the study area, leading to a lack of sedimentation in the region. The Yangtze River channel likely to pass by and supply sediments to the Yangtze shoal during sea level rise. This study provides valuable insights into the history of the Yangtze River channel and estuary since MIS 6, underscoring the river's significant role in shaping the sedimentary evolution of the western coast of the South Yellow Sea.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"664 ","pages":"Article 112813"},"PeriodicalIF":2.6,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143430153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Late Miocene carbonate-system evolution in the Xisha area, northern South China Sea","authors":"Feng Wu ,&nbsp;Zhimin Jian ,&nbsp;Xinong Xie ,&nbsp;Giovanni Coletti ,&nbsp;Youhua Zhu ,&nbsp;Zhilei Shang ,&nbsp;Beichen Chen","doi":"10.1016/j.palaeo.2025.112812","DOIUrl":"10.1016/j.palaeo.2025.112812","url":null,"abstract":"<div><div>Carbonate systems in tropical regions reliably record abundant palaeoenvironmental information. Sedimentological and paleontological data from the Upper Miocene interval of core XK-1, obtained after lithofacies classification and semi-quantitative fossil analysis, allow for a detailed documentation of the carbonate-system evolution in the Xisha area, South China Sea. The lower portion of the Upper Miocene interval is characterized by an alternation of patch-reef deposits and lagoonal bioclastic deposits, whereas the upper portion is dominated by lagoonal bioclastic deposits. Reefs increased gradually during the early Late Miocene as a result of eustatic sea level falls. The assemblage of red algae (<em>Mesophyllum</em>, <em>Lithothamnion</em>), benthic foraminifera (<em>Amphistegina radiata</em>, <em>Cycloclypeus</em>, <em>Heterostegina</em>, <em>Operculina</em>), and planktonic foraminifera preferring deeper waters in the upper portion of the Upper Miocene interval suggests a deepening trend, resulting from moderate increases in eustatic sea level and basement subsidence. Moreover, the prevalence of red algae, <em>Halimeda</em>, acervulinids, and bryozoans over corals after 7.1 Ma indicates the influence of elevated nutrient availability. The upwelling due to intensified East Asian Winter Monsoon could have contributed to the increase in nutrient availability. Our results demonstrate that eustatic sea level, tectonics, and monsoonal conditions jointly influenced the carbonate system in the Xisha area, South China Sea. These findings have broader implications for understanding the Late Miocene development of carbonate systems in this region.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"665 ","pages":"Article 112812"},"PeriodicalIF":2.6,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143454199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface and bottom water dynamics across the onset of the Messinian Salinity Crisis in the Piedmont Basin (NW Italy): Integrating micropaleontological and stable isotope evidence","authors":"A.M. Mancini ,&nbsp;E. Nallino ,&nbsp;F. Dela Pierre ,&nbsp;R. Gennari ,&nbsp;M. Natalicchio ,&nbsp;G. Carnevale ,&nbsp;G. Della Porta ,&nbsp;A. Negri ,&nbsp;F. Lozar","doi":"10.1016/j.palaeo.2025.112811","DOIUrl":"10.1016/j.palaeo.2025.112811","url":null,"abstract":"<div><div>The pace and nature of paleoenvironmental dynamics leading to the Messinian Salinity Crisis (MSC) remain debated, with conflicting interpretations from the fossil and geochemical proxies.</div><div>This study focuses on two key sections in the Piedmont Basin (NW Italy), Pollenzo and Govone, representing the northernmost Mediterranean sector during the Messinian. By implementing the previously published calcareous nannofossil assemblages with new data and analyzing carbon and oxygen stable isotopes from benthic and planktic foraminifers, this research aims at understanding surface and bottom water conditions around the MSC onset (5.97 Ma).</div><div>In this gypsum-free part of the basin, calcareous nannofossil abundance remained stable for ∼40 kyrs into the MSC, before disappearing, likely due to taphonomic bias. Isotopic records from the benthic foraminifer <em>Bolivina dilatata</em> suggest variations in living depth, remineralization, temperature and isotopic composition of water. Oxygen isotope data from planktic foraminifer show little variation between the 6.83–6.79 Ma and 6.05–5.99 Ma intervals, suggesting only moderate salinity and/or temperature fluctuations between the different time intervals.</div><div>These findings interpreted in the light of previous records—including organic geochemistry, fish, pollen, and dinocyst fossils pointing to salinity fluctuations between normal marine to brackish—suggest that hypersaline conditions did not characterize the early phase of the MSC in this part of the basin. These insights challenge the traditional view of widespread hypersalinity during the MSC onset, highlighting the need to integrate multiple datasets to better understand the Messinian environments in the Mediterranean Basin.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"664 ","pages":"Article 112811"},"PeriodicalIF":2.6,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Magnetic proxy in the Heqing drill core revealed Indian Summer Monsoon variations linked with AMOC at the orbital -scale during the late Pleistocene","authors":"Xinwen Xu ,&nbsp;Xiaoke Qiang ,&nbsp;Xubin Li ,&nbsp;Haijun Qiu ,&nbsp;Hui Zhao ,&nbsp;Chaofeng Fu ,&nbsp;Ziyi Yang","doi":"10.1016/j.palaeo.2025.112814","DOIUrl":"10.1016/j.palaeo.2025.112814","url":null,"abstract":"<div><div>Enhanced comprehension of the drivers behind the Indian Summer Monsoon (ISM) is imperative for advancing climate forecasting models. Current observations, climate models, and paleoclimatic data converge on the notion that ISM fluctuations are primarily modulated by shifts in the Intertropical Convergence Zone (ITCZ), which are themselves precipitated by the Atlantic Meridional Overturning Circulation (AMOC). In the epoch of the late Pleistocene, paleoclimate reconstructions have underscored a pronounced linkage between the circulation patterns of Indian Ocean and the vigor of the AMOC, observable across both millennial and orbital timescales. However, little attention has been paid to the linkage between the ISM and the AMOC at the orbital scale.</div><div>The extensive and continuous lacustrine sedimentary sequences from Southwest China serve as an unparalleled archive for charting evolutionary trajectory of the ISM. Guided by a refined chronological model forged through geomagnetic paleointensity analysis, the magnetic proxy measurements (ARM/SIRM) from the late Pleistocene evince the dominant precessional cycles. These are mirrored in ISM indicators gleaned from speleothems, lacustrine, and marine sediments across the ISM ambit. Intriguingly, at the precessional frequency, the ISM indicators march in lockstep with AMOC indicators, including the Agulhas Leakage Fauna (ALF) in core CD154-17 K, the δ¹³C in core MD02–2588, and the sea surface temperature (SST) gradient between the tropical and extratropical western Indian Ocean. This consistence lends credence to the hypothesis that ISM variability, propelled by ITCZ migrations, is coupled with the AMOC intensity at the orbital scale. The increased phase lags between Northern Hemisphere Summer Insolation (NHSI) and indicators of AMOC activity, ITCZ migration, ISM intensity suggested a non-negligible latitude differences in climate response to the internal forcing. The phase lag between ISM precipitation and NHSI might be indicative of accumulation of lags between ISM intensity and ITCZ migration, ITCZ migration and AMOC activity, AMOC activity and solar insolation.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"665 ","pages":"Article 112814"},"PeriodicalIF":2.6,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143454871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydroclimatic evolution of the southwestern Tibetan Plateau since the last glacial maximum inferred from multi-proxy data in Lake Zabuye","authors":"Yuan Ling ,&nbsp;Fangang Zeng ,&nbsp;James Bendle ,&nbsp;Jun Cheng ,&nbsp;Long Zhang ,&nbsp;Yong Wang ,&nbsp;Lijun Tian","doi":"10.1016/j.palaeo.2025.112809","DOIUrl":"10.1016/j.palaeo.2025.112809","url":null,"abstract":"<div><div>Hydroclimatic variations on the Tibetan Plateau since the Last Glacial Maximum (LGM) are still debated. Here, we reconstructed climatic and hydrological variability in the southwestern Tibetan Plateau since the LGM using climate proxies based on molecular distributions of <em>n</em>-alkanes, hydrogen (δD) and carbon (δ¹³C) isotopic compositions of terrestrial <em>n</em>-alkanes from sediments, and oxygen isotopic composition (δ¹⁸O) of authigenic carbonate at Lake Zabuye. The impact of climatic and environmental factors on these multiple proxies was discussed, and the TraCE-21 ka simulation was employed to facilitate a comprehensive model-data comparison. Our findings indicate that the δD of <em>n</em>C₃₁ alkane in this lake was primarily influenced by temperature from the LGM to early deglaciation period, shifting to a predominance of precipitation influence from the Heinrich event 1 (H1) to the Holocene period. In contrast, the carbonate δ¹⁸O was found to be primarily governed by evaporative processes. Through comprehensive analysis of all proxies, we suggest that Lake Zabuye was dominated by the mid-latitude westerlies with cold and moist conditions from the LGM to early deglaciation. The H1 and Younger Dryas events were characterized by low temperatures and reduced precipitation due to the influence of the moderately intensified westerlies. The Indian summer monsoon (ISM) intensified during the Bølling/Allerød period, and its strength was comparable to that of the westerlies, resulting in plentiful rainfall and high evaporation. The ISM was dominant during the Holocene, characterized by abundant rainfall and high evaporation.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"664 ","pages":"Article 112809"},"PeriodicalIF":2.6,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}