Palaeogeography, Palaeoclimatology, Palaeoecology最新文献

{"title":"Comparison of vegetation succession patterns in the monsoon and arid regions of northern China over the past two centuries: Implications for ecosystem restoration projects","authors":"Jiaqi Pang ,&nbsp;Guoqiang Ding ,&nbsp;Panpan Ji ,&nbsp;Yuanhao Sun ,&nbsp;Chuanyi Duan ,&nbsp;Yu Cao ,&nbsp;Jiheng Shi ,&nbsp;Ruijin Chen ,&nbsp;Jianhui Chen","doi":"10.1016/j.palaeo.2025.113295","DOIUrl":"10.1016/j.palaeo.2025.113295","url":null,"abstract":"<div><div>Understanding vegetation responses to climatic and anthropogenic changes is important for predicting future ecosystem trajectories and informing restoration projects in northern China. In this paper, we report high-resolution pollen records from Lake Gonghai (monsoon region) and Lake Yueliang (arid region) to investigate the relationship between vegetation, climate, and human activity over the past two centuries. Prior to 1900 CE, Lake Gonghai supported abundant arboreal vegetation under humid conditions, with extensive pastoralism indicated by high coprophilous fungal spores. During 1900–1960 CE, increasing aridity and social instability led to vegetation degradation and reduced pastoral intensity. After 1960 CE, ecological restoration policies promoted vegetation recovery, accompanied by a shift from pastoralism to <em>Hippophae</em>-dominated cultivation. In contrast, vegetation succession at Lake Yueliang has remained primarily climate-driven. Before 1900 CE, <em>Artemisia</em>–<em>Tamarix</em> desert–steppe communities prevailed under relatively humid conditions. During 1910–1990 CE, rising aridity induced a transition toward Amaranthaceae–<em>Nitraria</em> communities. After 1990 CE, persistent drought stabilized xerophytic vegetation composition. We suggest that vegetation dynamics across a large spatial scale have been (1) more strongly influenced by human activities in the monsoon region, with anthropogenic impacts intensifying since 1960 CE, and (2) primarily driven by climate in the arid region, with a west–to–east transition from warming–wetting to warming–drying. Our findings emphasize divergent regional ecosystem trajectories and the need for restoration strategies tailored to distinct climatic and anthropogenic contexts in northern China.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"679 ","pages":"Article 113295"},"PeriodicalIF":2.7,"publicationDate":"2025-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158833","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":"Dramatic biome changes in China through the Cenozoic Era: Modeling the combined effects of climate, CO2 concentration, and topography on long-term vegetation dynamics","authors":"Jie Xia ,&nbsp;Kai Li ,&nbsp;Mengna Liao ,&nbsp;Zihua Tang ,&nbsp;Dongmei Yang ,&nbsp;Jian Ni","doi":"10.1016/j.palaeo.2025.113297","DOIUrl":"10.1016/j.palaeo.2025.113297","url":null,"abstract":"<div><div>Past vegetation patterns and dynamics reflect changes to the environment, climate, and human disturbance over time. As such, they comprise potential analogues for vegetation development under future climate change scenarios. Simulations of global and regional vegetation patterns in the present and future are well established; however, such simulations, especially over geological time-scales, have been remain relatively rare for China. Here, we used proxy-based reconstructions of paleoclimate, atmospheric CO₂ concentration, and topography (including uplift of the Tibetan Plateau (TP)) to drive an improved version of the global vegetation model BIOME4-Asia. Our aim was to simulate paleovegetation changes across China throughout the Cenozoic and to examine the combined effects of these factors on long-term vegetation dynamics. The simulations revealed dramatic shifts in biome distribution and coverage under varying climatic, CO₂, and elevational conditions. Catastrophic regime shifts occurred in response to sudden, pronounced environmental changes during several intervals. Forest biomes expanded northward and westward, with increased coverage, during warm and humid climates, high <em>p</em>CO₂, and lower TP elevation, especially between 66 Ma and 40 Ma. Conversely, forests retreated southward, grassland and desert biomes advanced eastward, and dry tundra expanded on the plateau during colder and drier climates, reduced <em>p</em>CO₂, and higher elevations, particularly between 2 Ma and 21 ka. During other periods, simulated biomes broadly resembled modern distributions. Overall, climate change, atmospheric CO₂ concentration, and TP uplift jointly shaped vegetation dynamics in China during the Cenozoic, consistent with model simulations, pollen and macrofossil evidence, and phylogenomic studies. Incorporating paleoclimate data from advanced climate model simulations, paleotopography and land-sea reconstructions, and paleosol properties will be critical for reducing modeling uncertainties in future work.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"679 ","pages":"Article 113297"},"PeriodicalIF":2.7,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145109534","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":"Assessing Milankovitch forcing during and in the aftermath of the Early Eocene Climate Optimum: Dammam Formation, Saudi Arabia","authors":"Misbahu Abdullahi ,&nbsp;Taimur Khan ,&nbsp;Samer Aljurf ,&nbsp;Vagif Suleymanov ,&nbsp;Adhipa Herlambang ,&nbsp;Michele Morsilli ,&nbsp;Khalid Al-Ramadan ,&nbsp;Ardiansyah Koeshidayatullah","doi":"10.1016/j.palaeo.2025.113298","DOIUrl":"10.1016/j.palaeo.2025.113298","url":null,"abstract":"<div><div>The Eocene Epoch was a time of great climatic significance owing to its records of the Paleocene-Eocene Thermal Maximum (PETM), the Early Eocene Climate Optimum (EECO), and the Middle Eocene Climate Optimum (MECO). In the Arabian Plate, the EECO and its aftermath coincided with the development of the Lower to Middle Eocene Dammam Formation, a cyclic shallow-water carbonate ramp with meter-scale parasequences. Previous studies have shown the significance of Milankovitch forcing in pacing the Eocene events and deposition of sedimentary strata. However, the controlling process behind the high-resolution parasequences of the Dammam Formation remains enigmatic, particularly on the relative dominance between random and quasi-periodic Milankovitch forcing. To investigate this issue, we coupled continuous records of Spectral Gamma Ray (SGR), Magnetic Susceptibility (MS), and δ¹³C - δ¹⁸O data to assess the influence of astronomical forcing and the signature of how the Eocene climatic events are recorded in this formation. Results show that the overall low sedimentation rate recorded in the Dammam Formation is comparable with globally reported sedimentation rates of some shallow marine Eocene carbonates and compatible with low accommodation space on the Arabian carbonate ramp. Deposition was interpreted to be astronomically influenced based on the presence of eccentricity-paced parasequences, rejection of the null hypothesis (<em>p</em> &lt; 1 %), and the detection of Milankovitch cycles. The EECO event is detected within the shales and <em>Alveolina-Nummulitic</em> intervals of the Midra and Alveolina Limestone members of the formation. This study provides the first assessment of Milankovitch forcing during and after the EECO marine records of the Arabian Plate, which could be compared elsewhere.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"679 ","pages":"Article 113298"},"PeriodicalIF":2.7,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158834","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":"Origin and provenance of Lower Jurassic clastic rocks in the Badaowan Formation, Dachanggou Basin, Northern Xinjiang, China: Constraints on Early Jurassic weathering and depositional processes","authors":"Xingxuan Lei ,&nbsp;Pingchang Sun ,&nbsp;Junxian Wang ,&nbsp;Hongliang Dang ,&nbsp;Xuemei Tian ,&nbsp;Zhisheng Luan ,&nbsp;Zhuo Wang","doi":"10.1016/j.palaeo.2025.113293","DOIUrl":"10.1016/j.palaeo.2025.113293","url":null,"abstract":"<div><div>The Dachanggou Basin, a small intermontane basin in the southern Central Asian Orogenic Belt (CAOB), preserves high-resolution Early Jurassic clastic records of regional tectonics, orogenic uplift, and paleoclimatic changes. We integrate petrological, geochemical, and detrital zircon U-Pb data from the Badaowan Formation. Geochemical signatures demonstrate minimal alteration by sedimentary recycling, hydraulic sorting, or diagenesis. High Chemical Index of Alteration (CIA) values and sandstone petrography indicate moderate to strong chemical weathering. Geochemical data indicate that the Badaowan Formation was deposited in a post-collisional intracontinental rift basin, with mudstone (including oil shale) detritus primarily sourced from a felsic volcanic arc within a stable continental island arc setting. Sandstone petrology, dominated by felsic volcanic lithics and quartz, supports this interpretation. Detrital zircon ages reveal three dominant populations and minor Proterozoic groups, recording multiple magmatic episodes with limited ancient recycling. The 530–480 Ma zircons derive from Cambrian arcs north of East Junggar and Permian Bogda Mountain sediments. The 430–390 Ma and 360–270 Ma groups correlate with magmatism in the Yemaquan and Bogda arcs. The youngest zircon at 250 Ma suggests that Indosinian orogenesis in East Junggar began no earlier than this time. Provenance shifted from proximal Yemaquan Arc to distal Bogda Arc during the Early Jurassic, coinciding with increasingly warmer, more humid climatic conditions. This transition implies tectonic uplift and erosional exhumation of the eastern Bogda Orogenic Belt (BOB) by the late deposition stage of the Badaowan Formation.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"679 ","pages":"Article 113293"},"PeriodicalIF":2.7,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158836","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":"Silent past: Biogeographic gaps in the Cenozoic fossil archive","authors":"Marta Matamala-Pagès ,&nbsp;Oskar Hagen ,&nbsp;Adrián Castro-Insua ,&nbsp;Adriana Oliver ,&nbsp;Eduardo Méndez-Quintas ,&nbsp;Graciela Sotelo ,&nbsp;Iván Rey-Rodríguez ,&nbsp;Sara Gamboa ,&nbsp;Sofía Galván ,&nbsp;Sara Varela","doi":"10.1016/j.palaeo.2025.113296","DOIUrl":"10.1016/j.palaeo.2025.113296","url":null,"abstract":"<div><div>Exposed sedimentary rocks are unevenly distributed across space, interfering in our ability to reconstruct the spatial and temporal dynamics of past climates and ecosystems. In this study, we quantified the extent of “lost” informative areas—regions where sedimentary layers from the past 66 million years (Ma) are not presently exposed—and assessed gaps across climate zones and geological time bins. Using Chorlton's global geological map, we reconstructed the distribution and depositional ages of exposed sedimentary rocks, and linked these with palaeoclimate simulations from the HadCM3 model, classified under the Köppen–Geiger system. This framework allowed us to compare the distribution of palaeoclimates predicted by HadCM3 for each time bin with the distribution of climates represented only by currently exposed rocks of that interval. We further integrated fossil occurrence data from the Paleobiology Database (PBDB) to evaluate mismatches between climatic coverage in the geological and fossil records. Our results indicate that more than 72 % of past continental areas across the Cenozoic lack accessible sedimentary rocks, implying a substantial loss of information about past biodiversity. Of the remaining 28 %, exposed sediments are disproportionately derived from regions that experienced tropical, temperate, and arid climates, while deposits from cold and polar climates are underrepresented. The fossil record, in contrast, shows distinct biases, with a particularly large proportion of fossils originating from past temperate environments, likely reflecting excavation effort. These findings underscore the need to account for geographic and climatic biases when interpreting macroevolutionary trends, biodiversity patterns, and species' responses to climate change.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"679 ","pages":"Article 113296"},"PeriodicalIF":2.7,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145109533","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":"Trait-space disparity in fish communities spanning 380 million years from the Late Devonian to present","authors":"John Llewelyn ,&nbsp;John A. Long ,&nbsp;Richard Cloutier ,&nbsp;Alice M. Clement ,&nbsp;Giovanni Strona ,&nbsp;Frédérik Saltré ,&nbsp;Michael S.Y. Lee ,&nbsp;Brian Choo ,&nbsp;Kate Trinajstic ,&nbsp;Olivia Vanhaesebroucke ,&nbsp;Austin Fitzpatrick ,&nbsp;Corey J.A. Bradshaw","doi":"10.1016/j.palaeo.2025.113294","DOIUrl":"10.1016/j.palaeo.2025.113294","url":null,"abstract":"<div><div>The diversity and distribution of species' traits in an ecological community determine how it functions. While modern fish communities conserve trait space across similar habitats, little is known about trait-space variation through deep time or across different habitats. We examined how fish trait diversity varies through space and time by comparing three Late Devonian fish communities — a tropical reef (Gogo, Australia), a tropical estuary (Miguasha, Canada), and a temperate freshwater system (Canowindra, Australia) — with six modern communities from diverse habitats. Trait-space metrics reflecting within-community diversity (functional richness) and species similarity (functional nearest-neighbour distance) indicated Late Devonian communities had scores similar to modern communities. However, they were less functionally rich than their closest modern analogues, and their species tended to be more functionally distinct from one another. Metrics describing location in trait space (centroid distances and hypervolume overlap) showed modern communities were similar to each other, Gogo and Miguasha were similar but distinct from modern communities, and Canowindra was distinct from all others. This pattern suggests period-associated differentiation and substantial heterogeneity among some Late Devonian communities. In addition to temporal changes, we found consistent differences associated with habitat type and climate zone. Reef and tropical communities were the most functionally rich, whereas functional nearest-neighbour scores were highest in estuarine and temperate communities. These results indicate fish community trait space varies with time, habitat and climate, suggesting (<em>i</em>) lability in fish trait space and (<em>ii</em>) that evolutionary history, environmental filtering, and stochasticity influence community assembly.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"679 ","pages":"Article 113294"},"PeriodicalIF":2.7,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145221141","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":"Epibiosis and epifaunal tiering in brachiopods from the Cambrian Xiaoshiba Lagerstätte of China","authors":"Yu Wang ,&nbsp;Paul D. Taylor ,&nbsp;Jie Yang ,&nbsp;Xiguang Zhang","doi":"10.1016/j.palaeo.2025.113292","DOIUrl":"10.1016/j.palaeo.2025.113292","url":null,"abstract":"<div><div>In the early Cambrian, brachiopods quickly became a distinctive group of the marine community and played a key role in the increasingly diversified benthic ecosystem. Based on new material from the Cambrian Stage 3 Xiaoshiba Lagerstätte, we focus on brachiopods displaying epibiotic relationships and tiering attachment to demonstrate: 1) abundant individuals of <em>Kutorgina chengjiangensis</em> once acted as the predominant components to construct the cohesive substrate, which were often selected by epibionts as their hosts for shallow-sea inhabitation, exhibiting a symbiotic association; 2) within the same community, the secondary tierers are well recorded at least by some of acrotretoid brachiopods attaching to gregarious tubes of <em>Tubulella</em> sp. Our findings give additional evidence for illuminating the unexpected complexity of the palaeoecosystem and clarifying the rapid adaptive radiation and ecological niche expansion associated with early Cambrian brachiopods.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"679 ","pages":"Article 113292"},"PeriodicalIF":2.7,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145096876","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":"RAD-seq reveals Cenozoic shifts in the palaeogeographic distribution of Trigonobalanus verticillata across the Indochina Peninsula and Malay Archipelago","authors":"Ling Hu ,&nbsp;Pei-Han Huang ,&nbsp;Yi-Gang Song ,&nbsp;Shook Ling Low ,&nbsp;Guo-Xiong Hu ,&nbsp;Shi-Shun Zhou ,&nbsp;Lang Li ,&nbsp;Yun-Hong Tan ,&nbsp;Hong-Hu Meng ,&nbsp;Yu-Peng Cun ,&nbsp;Jie Li","doi":"10.1016/j.palaeo.2025.113291","DOIUrl":"10.1016/j.palaeo.2025.113291","url":null,"abstract":"<div><div>The complex geological history and rich biodiversity of Southeast Asia have long fascinated biologists, ecologists, and biogeographers. In this paper, we address the spatiotemporal patterns of genetic diversity and dispersal dynamics of <em>Trigonobalanus verticillata</em> across the Indochina Peninsula and Malay Archipelago since the early Cenozoic and project distribution range shifts into the future. Our work is based on the integration of RAD-seq data with ecological niche modeling, to assess genetic diversity, genetic structure, divergence timing, and demographic dynamics. The key findings are as follows: (1) the species originated in north Sundaland, i.e., Indochina Peninsula, in the late Eocene, followed by Oligocene-Miocene stepwise south and northward dispersal events, establishing allopatric lineages via the Indochina Peninsula to the Yunnan and Hainan Island, while also expanding across Borneo to other regions of the Malay Archipelago. (2) Tectonically-driven habitat heterogeneity and inter-refugial gene flow promoted high genetic diversity in the Indochina Peninsula, whereas historical bottlenecks reduced genetic diversity in the Malay Archipelago. (3) Borneo served as a persistent region of refugial suitability from the Last Glacial Maximum to the present and is expected to retain its refugial function in the future. Our findings elucidate how Neogene-Quaternary environmental changes shaped contemporary biodiversity patterns in Southeast Asia, underscoring Borneo's critical role in conservation being a long-term refuge that has sustained the evolutionary potential of the species. Our integrative approach also provides a framework for understanding regional biogeographic dynamics through the genomic-level history of <em>T. verticillata.</em></div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"679 ","pages":"Article 113291"},"PeriodicalIF":2.7,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145096878","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":"Monsoonal intensity dominated the Eocene evolution of paleovegetation and paleoclimate in northern South China Sea","authors":"Jinhua Zeng ,&nbsp;Tao Jiang ,&nbsp;Keqiang Wu ,&nbsp;Desheng Hu ,&nbsp;Yong Man ,&nbsp;Licheng Cao ,&nbsp;Cong Cheng ,&nbsp;Zigui Chen ,&nbsp;Kun Wang ,&nbsp;Nan Bai ,&nbsp;Meiling Feng ,&nbsp;Ziyi Li","doi":"10.1016/j.palaeo.2025.113288","DOIUrl":"10.1016/j.palaeo.2025.113288","url":null,"abstract":"<div><div>The East Asian climate system experienced profound transformation throughout the Eocene epoch, characterized by spatial differences in paleoclimate evolution. However, continuous records of Eocene climate remain scarce, and the driving mechanisms are poorly understood, particularly in low-latitude regions. The Weixinan Sag in the northern South China Sea documents vegetation dynamics and weathering regimes through its continuous clastic sedimentary sequences. Based on palynological records and geochemical proxies from the Eocene Liushagang Formation in the Weixinan Sag, this study suggests a triphasic climatic evolution in the northern South China Sea. During the early Eocene, the Weixinan Sag was dominated by floodplain deciduous broad-leaved forests and montane coniferous forests under moderate weathering conditions, signaling a subtropical monsoon climate. By the middle Eocene, enhanced rainfall triggered peak humidity with intense chemical weathering, alongside the development of evergreen-deciduous broadleaved forests in lowlands and mixed forests in highlands. During the late Eocene, aridification resulted in fern expansion and diminished weathering, yet residual rainfall rhythms persisted. Paleovegetation landscapes and chemical weathering intensity, marked by seasonal precipitation fluctuations, confirm operational monsoonal circulation since the early Eocene and demonstrate the dominance of monsoonal circulation in the Eocene climate of the northern South China Sea. Weak coastal proto-monsoonal cells initiated in early Eocene low-latitude coastal areas through greenhouse-enhanced land-sea thermal gradients, matured into a continental-scale system during middle Eocene paleogeographic restructuring, and then attenuated in the late Eocene due to the effects of global cooling on thermal gradients overriding that of paleogeographic changes. These findings not only reveal the Eocene climatic evolution and driving mechanisms in low-latitude regions, but also recalibrate the developmental chronology of the Eocene East Asian summer monsoon.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"679 ","pages":"Article 113288"},"PeriodicalIF":2.7,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145096877","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":"Orbital-scale competition of biogenic carbonate and opal production and its implication on carbon cycle at Del Caño Rise in the Indian sector of the Southern Ocean","authors":"Hyuk Choi ,&nbsp;Xavier Crosta ,&nbsp;Isabelle Billy ,&nbsp;Tomohisa Irino ,&nbsp;Sangbeom Ha ,&nbsp;Hiroyuki Takata ,&nbsp;Boo-Keun Khim","doi":"10.1016/j.palaeo.2025.113290","DOIUrl":"10.1016/j.palaeo.2025.113290","url":null,"abstract":"<div><div>Geochemical properties measured in core MD19-3575CQ, collected from the Del Caño Rise within the Subantarctic Zone in the Indian sector of the Southern Ocean, provide evidence of orbital-scale changes over eccentricity, obliquity, and precession cycles in phytoplankton productivity and its influence on the organic matter burial over the last 235 kyr. CaCO₃ and biogenic opal contents varied oppositely with high CaCO₃ and low biogenic opal contents during the interglacial periods and <em>vice versa</em> during the glacial periods. During the glacial periods, the biogenic opal production by diatoms increased as a result of more silica supply when the Subantarctic Front shifted northward across the Del Caño Rise. In addition, Fe-bearing dust and remobilized sediments likely enhanced diatom productivity. In contrast, biogenic carbonate production by coccolithophores and foraminifera was reduced during the glacial periods because of cold ocean temperature and competition for nutrients between coccolithophores and diatoms. More organic carbon was buried at the core site during the glacial periods than during the interglacial periods, probably in relation to a greater export efficiency by diatoms relative to coccolithophores as well as a better preservation of the organic matter when the Circumpolar Deep Water was less ventilated during the glacial periods.</div></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"679 ","pages":"Article 113290"},"PeriodicalIF":2.7,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145096931","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}