Growing evidence indicates that glacial cycles influence volcanic activity, yet the physical mechanisms linking glaciation to magmatic processes in continental arcs remain unclear. We integrate realistic ice and topographic loads with a dike model to evaluate how glaciation modulated magma ascent beneath Mocho-Choshuenco, Chile, during the Last Glacial Maximum (LGM). Ice loading generates a crustal stress "pinch point" that causes dikes rising from lower-crustal reservoirs to stall deeper than under ice-free conditions, effectively shutting off recharge to shallow magma reservoirs. This mechanism explains the ~2-3 km increase in magma storage depth and reduced eruption rates during the LGM without invoking changes in mantle melt supply or reservoir strength. Shutting off recharge also favors magma differentiation, setting the stage for more explosive silicic eruptions during deglaciation once recharge resumes. We identify a parsimonious explanation for glacially-driven shifts in magma composition, storage depth, and eruption rate at Mocho-Choshuenco and arc volcanoes worldwide.

Phytoliths, pollen, and spores in a stratigraphic sequence from the Shishan Wetland (Azraq Basin, Jordan) and supported by modern pollen and phytolith data provide information on vegetation, climatic trends, and the influence of fire through MIS 2 and MIS 1. Additionally, a pilot study introduces an innovative approach that uses shape and morphometric parameters of Bulliform phytoliths to assess hydro-climatic changes. The phytolith terrestrial–aquatic ratio, grass–pollen size, and the Artemisia–Amaranthaceae ratio (A:C) indicate that during the Last Glacial Maximum (LGM), the study area was a wetland surrounded by steppe, and that during the deglaciation period (c. 20–11 ka), the wetland vegetation remained almost unchanged but the surrounding area tended to aridity. The phytoliths’ terrestrial ratio, the presence of C4 grass phytoliths, and the low A:C is characterized by a reduced wetland and the establishment of a hot desert, like the present. The record at Shishan Marsh shows effective moisture trends concurrent with other records in the western southern Levant, but climatic events (Heinrich Stadial 1 and Younger Dryas) are not recorded because of the low time-resolution of the studied sequence. This study shows that combining pollen and phytoliths strengthens vegetation reconstruction by discerning local from regional floristic components and that Bulliform phytoliths are a potential tool to reconstruct hydro-climatic conditions.

Victoria Land, along the western Ross Sea coast in Antarctica, provides critical insights into past glacial and climatic changes, which may be helpful to refine projections of future environmental shifts. This study refines estimates of ice thickness since the Last Glacial Period in Terra Nova Bay by integrating geomorphological, geological, and geochronological datasets, and delineates the formation of the “Terra Nova Ice Sheet/Shelf”, which resulted from the merging of outlet glaciers in the bay. Enhanced and thickened glacial discharge from the southwest sculpted the Drygalski Trough, forcing smaller outlet glaciers to merge and redirect northeastward as a unified ice body. The grounded ice sheet extended over Cape Washington, as evidenced by granitoid erratics deposited on the peninsula. Cosmogenic nuclide (in situ 10 Be and 26 Al) surface exposure dating indicates that ice thinning began before the LGM (Last Glacial Maximum), with a Local LGM occurring earlier. Subsequent rapid ice lowering took place in the mid‐Holocene, driven by Marine Ice Sheet Instability and delayed by the stepwise retreat of the grounded ice in the Ross Sea. These findings underscore the complexity of Antarctic ice dynamics and highlight that regional ice shelf behavior, rather than temperature alone, is a primary driver in ice mass changes.

Abstract. Density of seawater is a critical property that controls ocean dynamics. Previous works suggest the use of the δ18O calcite of foraminifera as a potential proxy for paleodensity. However, potential quantitative reconstructions were limited to the tropical and subtropical surface ocean and without an explicit estimate of the uncertainty in calibration model parameters. We developed the use of the δ18Oc of planktonic foraminifera as a surface paleodensity proxy using Bayesian regression models calibrated to annual surface density. Predictive performance of the models improves when we account for inter-species specific differences. We investigate the additional uncertainties that could be introduced by potential evolution of the δ18Oc-density relationship with time – from the last glacial maximum (LGM) to the preindustrial (PI) – through the combination of past isotope enabled climate model simulations and a foraminiferal growth module. We demonstrate that additional uncertainties are weak globally, except for the Nordic Seas region. We applied our Bayesian regression model to LGM and Late Holocene (LH) δ18Oc foraminifera databases to reconstruct annual surface density during these periods. We observe stronger LGM density value changes at low latitudes compared to mid latitudes. These results will be used to evaluate numerical climate models in their ability to simulate ocean surface density during the extreme climatic period of the LGM. The new calibration has great potential to reconstruct the past temporal evolution of ocean surface density over the Quaternary. Under climates outside the Quaternary period and in ocean basins characterized by anti-estuary circulation, like the current Mediterranean Sea and Red Sea, our calibration could provide density estimates with larger uncertainty, a point that requires further investigations.

ABSTRACTThe Qinghai‐Tibet Plateau (QTP) is a global biodiversity hotspot where Quaternary climatic oscillations profoundly shaped the evolution of endemic alpine flora. Understanding how genetic diversity and structure in these species responded to past climate change is crucial for deciphering regional evolutionary mechanisms. Using chloroplast and nuclear genome data of 958 samples from 48 populations, we evaluated the genetic diversity and population structure of Primula sikkimensis. We then investigated the lineage differentiation and dynamics of species by combining an Approximate Bayesian Computation procedure and species distribution modeling. Our study indicates that P. sikkimensis maintained separate glacial refugia in the Hengduan Mountains and eastern Himalayas during the Last Glacial Maximum (LGM). Our results suggest that postglacial range expansions onto the inner QTP plateau were accompanied by gene flow arising from both intraspecific secondary contact between previously isolated populations and interspecific hybridization events, which collectively enhanced genetic diversity and adaptive capacity in plateau populations. Our findings underscore the critical role of postglacial population dynamics and gene flow in shaping genetic diversity and adaptive potential of alpine endemics like P. sikkimensis, highlighting evolutionary responses to Quaternary climate change on the QTP.

The piedmont glacial landforms on the northern foothills of the Central Himalayas provide critical records of the Last Glacial Maximum (LGM) glaciation, yet the glacier–environment interactions in the Yarlung Zangbo River source region (SYZR) remain poorly constrained. Integrating field surveys, remote sensing, a previously established chronological and glacier reconstruction framework, and a coupled Precipitation-Temperature (P-T) model, this study systematically reconstructs the LGM paleoclimate and investigates its climatic-topographic drivers. Key findings include the following: (1) 20 piedmont glaciers covered 4000 km 2 during the LGM, 9.6 times of modern extent, with the largest lobes in Jiemayangzong and Kubiqu basins; (2) glacier scales show strong negative correlations with basal elevation (5000–5100 m) and slope (<10°), while resistant leucogranite bedrock preserved high divides by attenuating the “glacial buzzsaw” effect; (3) the P-T modeling reveals an Equilibrium-Line Altitudes (ELA) depression of 357 ± 169 m, a temperature decrease of 1.6 to 4.6°C, and a precipitation reduction of 10% to 28% during the LGM compared to modern levels. Topographic gaps that funneled moisture created significant spatial heterogeneity in glacier morphological characteristics. This study quantitatively resolves the LGM climate sensitivity of Himalayan piedmont glaciers, highlighting synergistic controls of regional climate forcing with local topography, lithology, and moisture availability.

Fagus longipetiolata Seemen and Fagus lucida Rehder & E.H. Wilson are the dominant species in subtropical deciduous broad-leaved forests of China, playing crucial ecological and economic roles. As ecologically and economically important trees, it is critical to understand their responses to climate change. This study employed MaxEnt modeling to discover the range shifts from their historical distributions to future projections. The distribution of suitable habitats of F. longipetiolata is more affected by precipitation, and that of F. lucida is more sensitive to temperature. High-suitability habitats for both species were concentrated predominantly in the Yangtze River Basin. While both species showed substantial distribution centroid shifts since the Last Glacial Maximum (LGM), F. lucida exhibited greater habitat fragmentation and more pronounced reductions in high-suitability areas under projected climate change compared to F. longipetiolata. Our results suggest that despite close phylogenetic relationships, these sister species face divergent climate change threats, with F. lucida being more vulnerable. These findings not only advance the conservation strategies for F. lucida but also provide critical insights for mitigating the impacts of intensifying global warming on subtropical forest ecosystems.

Due to the complexity of sedimentary evolution since the Last Glacial Maximum (LGM) in the Yangtze River Estuary (YRE), sedimentary responses across different regions have varied significantly, but the sedimentary record on the northern flank of the estuary remains incomplete. Here we integrate analyses of sedimentology, chemical weathering indices (CIA and K/Al), total organic carbon (TOC), and organic carbon isotopes (δ 13 C org ) from the QDQ2 core to reconstruct the regional environmental evolution from 36.1 to 8.4 cal kyr BP. Facies analysis demonstrates that QDQ2 succession documents environmental shift from terrestrial distributary channels to marine delta fronts. Sedimentary evidence of marine transgression during the Last Deglacial Period is identified, and facies shifts were driven by climate events and sea-level variations. Furthermore, the Gehu transgression did not influence the facies succession of study area. Instead, variations in CIA and K/Al ratios indicate modification in the hinterland chemical weathering intensity, likely driven by the warm climate characteristics of Marine Isotopic Stage 3a (MIS 3a).

The Yan goose (YE, Anser cygnoides) is a valuable indigenous poultry genetic resource, renowned for its superior meat quality and environmental adaptability. Despite its economic importance, the genetic basis underlying these adaptive traits remains unclear. In this study, we employed whole-genome resequencing (WGS) to perform high-throughput sequencing on a conserved population of 15 samples. Bioinformatic analyses were conducted to systematically evaluate the population's genetic structure, and a genome-wide scan for selection signals related to economically significant traits was performed using the integrated haplotype score (iHS) method. An average of 4.43 million high-quality SNPs were identified, which were predominantly located in intergenic and intronic regions. Population structure analysis revealed a close genetic relationship within the conserved population of YE, with no significant lineage stratification observed. Pairwise sequentially Markovian coalescent (PSMC) analysis indicated that the YE underwent a severe genetic bottleneck during the Last Glacial Maximum (LGM), followed by gradual population recovery in the early Neolithic period. Genome-wide selection signal scanning identified multiple genomic regions under strong selection, annotating key genes associated with growth and development (e.g., GHRL, AKT1, and MAPK3), lipid deposition (e.g., PLPP4, SAMD8, and LPIN1), and disease resistance and stress resilience (e.g., TP53, STAT3). Functional enrichment analysis revealed significant enrichment of these genes in pathways related to glycerophospholipid metabolism (p < 0.01), purine metabolism (p < 0.01), and immune response (p < 0.01). This study not only provides a theoretical foundation for the scientific conservation of the YE germplasm resources but also offers valuable genomic resources for identifying functional genes underlying important economic traits and advancing molecular breeding strategies.

The climate dynamics and driving mechanisms of the East Asian Summer Monsoon (EASM) in the Yangtze River Delta (YRD) since the Last Glacial Maximum (LGM) remain uncertain. We reconstruct annual mean temperature (Tann), mean temperature of the warmest month (MTwa), and annual mean precipitation (Pann) since 19.4 ka BP in the Yangtze River Delta (YRD), using pollen records from three sediment cores (LZK1, CSJA6, ZKA4), constrained by AMS ¹⁴C and OSL dating. Reconstructions were performed with a pollen–climate model based on the Locally-Weighted Weighted-Averaging (LWWA) method. Additional sedimentary proxies (grain size and magnetic susceptibility) were integrated to evaluate climate dynamics and forcing factors. Five climatic stages were identified: the LGM (19.4–18.0 ka, cold–dry), deglaciation (18.0–11.7 ka, fluctuating warming), early Holocene (11.7–8.2 ka, warm–humid), mid-Holocene (8.2–4.2 ka, warm–humid), and late Holocene (after 4.2 ka, fluctuating cooling). These stages broadly align with EASM intensity variations. Abrupt events (Heinrich 1, Bølling–Allerød, Younger Dryas, 8.2 ka, and 4.2 ka) were synchronous with Greenland ice core and Yangtze River stalagmite records, reflecting global climate teleconnections. On the millennial scale, EASM variability was controlled by Northern Hemisphere summer insolation, Atlantic Meridional Overturning Circulation (AMOC), and ice-volume/sea-level feedbacks. On the centennial scale, it was influenced by solar activity, volcanic eruptions, and the El Niño–Southern Oscillation (ENSO). These findings provide high-resolution evidence of EASM dynamics and offer a valuable reference for understanding regional climate adaptation in the future.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-33476-8.

Salahnama and Pandang Islands lie on the main range of the granite province; both islands are located in the Sunda Shelf, Malacca Straits. These islands are composed of intrusive rocks from Berhala. The rock’s existence will offer a significant contribution to the distribution of surface sediments in the surroundings. The sea dynamics and the geometry of the Malacca Strait will also have an impact on the seabed. Apart from that, global factors such as sea level changes will lead to transformation of the depositional environment and subsurface geology in the strait. Geological conditions of the seabed surface and subsurface can be understood and interpreted based on the acoustic characteristics and reflector patterns of a seismic section. Then, based on the acoustic character and reflector pattern, an acoustic facies can be defined. Seismic data measurements have been carried out around Salahnama and Pandang Islands in 2024. Based on the results of the seismic section, the acoustic facies in the study area are classified into 6 (six), which include AF I – AF VI. Seabed morphological features in the form of sand dunes were identified in the first acoustic facies (AF I); this feature is formed due to geometric aspects, surface currents, and bottom current's which may or may not be triggered by tidal vortices. Acoustic Facies II (AF II) is characterized by sandwave or ripple marks formed by strong seabed currents. AF III was formed after the Last Glacial Maximum (LGM) ended and the depositional environment returned to a shallow marine environment, characterized by a transparent pattern in the seismic section. The erosional truncation at the upper boundary of AF IV indicates a change in the depositional environment from shallow marine to coastal or terrestrial environments during the Last Glacial Maximum period. AF V is acoustic bedrock, and AF VI is characterized by a chaotic pattern, which is interpreted as granitic intrusive rocks.

The family Pieridae (Lepidoptera: Pieridae) is known for its ecological and conservation significance; however, little is known about its spatial distribution pattern and climate vulnerability in mainland China, complicating the formulation of effective conservation strategies. Pierinae and Coliadinae are widely distributed across most parts of the research zone, especially in the southern regions. Conversely, Dismorphiinae is mainly distributed in the west-central and northeastern parts. Pierinae and Coliadinae flourished over a wider range of elevations in open environments with warmer and more humid habitats, whereas Dismorphiinae is restricted to a narrow elevation range in forested areas with cooler and drier habitats. Therefore, it was necessary to study their distribution patterns separately. The MaxEnt model was applied to analyze the influence of bioclimatic variables on their distribution throughout three historical eras: the Last Interglacial (LIG), the Last Glacial Maximum (LGM), and the Current (1970-2000). Pierinae and Coliadinae showed a uniform increase in overall highly suitable habitats, while Dismorphiinae showed an initial increase and then a decrease. Due to global warming, all three subfamilies might experience contraction in highly suitable habitats. Most Pieridae species are projected to experience shrinkage in highly suitable habitats, leading to decreased species diversity. These findings highlight divergent historical distribution patterns and habitat preferences among Pieridae subfamilies, yet project a shared vulnerability to future habitat contraction under climate warming.

ABSTRACT During the last glacial maximum (LGM), the Yangtze River drained the exposed East China Sea shelf and discharged into the Okinawa Trough. Determining the extent of the ancient Yangtze sediment‐routing system and the precise location of its palaeo‐mouth at the shelf edge is crucial for understanding the Yangtze's source‐to‐sink processes, characterising the architecture and sedimentology of the shelf‐edge delta and reconstructing shelf palaeogeography. Here, an integrated survey of geochemistry, grain size and benthic foraminiferal assemblages was conducted on bottom sediments from the shelf margin. We utilise chemical approaches to discriminate sediment sources, evaluate hydrodynamic‐sorting effects and extract geomorphic information. Sub‐bottom seismic profiles and high‐resolution bathymetric data further aid in identifying shelf‐edge geomorphology and seafloor topography. Our results indicate that shelf‐edge sediments are predominantly derived from the Yangtze River. The influence of fine‐grained Old Yellow River sediments is discernible in the northwestern study area, adjacent to the outer‐shelf mud patch southwest of Cheju Island, marked by a reduced K/Rb ratio. A sharp increase in K/Rb within lowstand shoreface sands reflects mineral sorting due to prolonged wave action. The LGM shorelines are further constrained by an enrichment of porcelaneous benthic foraminifera along the 120‐m isobath. Elevated Zr/Y ratios delineate the spatial extent of the palaeo‐Yangtze sediment‐routing system across the shelf. The inferred probable location of the LGM Yangtze mouth, though lack of precise direct dating, lies between 28.5°N–28.9°N and 126.3°E–126.5°E, tracing the 120 m isobath. This was a large, tide‐dominated estuary with braided channels. A southwestward‐flowing coastal current dominated the shelf edge during this period. Abundant calcareous bioclasts and elevated benthic foraminiferal diversity in the estuarine sediment indicate a high productivity during the LGM. As sea level rose gradually, the palaeo‐mouth retreated northwestward before shifting to another palaeo‐estuary near the 100 m isobath, immediately preceding Meltwater Pulse 1A ~14 600 years ago.

Abstract The relationship between changes in surface air temperature and sea surface temperature is important for understanding past and future climate change. In this study, we use reconstructions and model simulations to investigate the ratio of global mean air versus sea surface temperature change ( S ) during the Last Glacial Maximum (LGM). The simulated S at the LGM is 1.97 ± 0.22 (1σ), 44 ± 16% greater than under future warming, primarily due to the influence of elevated continental ice sheets. Results reveal that the glacial air‐sea cooling contrast is negatively related to the magnitude of sea surface cooling, consistent with a simple moist static energy theory. This relationship can be used to constrain S , further suggesting a median LGM surface cooling of −5.6°C. These results caution against the use of a fixed S under different climate background and have implications for paleotemperature reconstructions and climate projections.

IntroductionAs a treasured wild plant resource in the Tian shan Mountains, the genetics and evolutionary relationships of Xinjiang wild walnuts (Juglans regia L.) are of great interest for both walnut conservation and crop improvement.MethodsIn this study, a total of 200 walnut accessions, including a core germplasm collection of wild walnuts from Xinjiang and local walnut landraces and cultivars, were selected for whole-genome resequencing, with the final dataset supplemented with 24 other publicly available genomic datasets for other walnut taxa.ResultsAcross all samples, there was evidence of four ancestral genetic populations, with three of these represented in the samples from Xinjiang. The Xinjiang wild walnuts form an independent evolutionary clade with low genetic diversity, which was further differentiated into six subgroups, and showed significant genetic differentiation from the cultivated accession. The walnut cultivars and landraces showed mixed ancestry, being assigned to two ancestral populations not represented in the wild walnuts. The Gongliu Wild Walnut Valley served as one of the refugia during the Last Glacial Maximum (LGM) for Tertiary relict species. The unique topography of the Ili River Valley in Xinjiang, along with the relatively isolated geographical location of the Walnut Valley, may have collectively facilitated the formation of a relatively isolated “genetic island” pattern in the Xinjiang wild walnuts. Selective sweep analysis identified 20 genes under selection, including CYP450 genes closely associated with disease resistance and NF-YB3 genes involved in cold stress and other adaptive responses.DiscussionA new framework is needed to reconceptualize the genetic relationships of Xinjiang wild walnuts with other germplasms, clarifying their continuous role throughout the evolutionary continuum from glacial refugium to domestication and modern breeding.

BackgroundLiquidambar orientalis, a relict and endemic tree species of the Eastern Mediterranean, is increasingly threatened due to its narrow distribution and intense anthropogenic pressures. This study aims to model the spatiotemporal changes in its habitat suitability from the Last Glacial Maximum (LGM) to future climate scenarios (2050 and 2070) using a robust ensemble species distribution modeling (SDM) framework. By integrating paleobotanical data with predictive modeling, we provide crucial insights into the species' ecological resilience and future conservation priorities.ResultsThe ensemble models showed excellent predictive performance (AUC = 0.96, TSS = 0.91, Boyce Index = 0.84, Kappa = 0.89), identifying mean diurnal range (Bio2) and precipitation of coldest quarter (Bio19) as the most influential variables. Fossil pollen records confirm the species long–term persistence in southwestern Anatolia since the early Miocene. While projections under the RCP 2.6 scenario suggest potential habitat expansion or stability, especially in mountainous refugia, the RCP 8.5 scenario indicates a reduction in highly suitable areas. Nevertheless, key ecological niches are expected to persist, particularly along the southern slopes of the Taurus Mountains.ConclusionsThis is the first study to combine multi temporal ensemble SDMs and fossil records for L. orientalis, revealing its ecological flexibility over millennia. The findings underscore the necessity of prioritizing genetically diverse populations and climatically stable refugia in conservation strategies. Our integrative approach provides a valuable framework for assessing the climate resilience of other Mediterranean relict species.

Abstract Genomic studies are crucial for understanding plant diversity, evolutionary history, and drivers of evolutionary change, as plant genomes carry signatures of these processes. The heterogeneous mountain and river systems have significantly impacted the evolution and divergence of plants, yet few comprehensive studies have investigated how such landscapes shape genetic diversity, population structure, and evolutionary trends. We explored the phylogeography of Debregeasia orientalis C.J.Chen (Urticaceae), a key native species of southwestern China’s unique landscape, known for its ecological significance and importance in traditional Chinese medicine. We investigated the phylogeography and evolutionary history of D. orientalis using chloroplast (cp) genome and nuclear ribosomal DNA (nrDNA) region data and ecological niche modelling (ENM). Genetic data from 79 populations and 283 individuals revealed the presence of two major clades designated as Clade A and Clade B, along with nine sub-clades (A1–A3 and B1–B6). The divergence time between the two major clades (A and B) is estimated to be about 0.83 Ma (95% HPD = 0.51–1.24 Ma) during the Pleistocene. Debregeasia orientalis populations exhibited high genetic diversity and an expanded distribution range since the Last Glacial Maximum (LGM), with projections into future scenarios. ENM results identified priority conservation regions in the provinces of Guizhou, Yunnan, and Taiwan, where the species distribution remained stable across different periods. The results reveal how the complex geographical and climatic factors have shaped the D. orientalis phylogeography since the LGM. This study highlights the significance of the heterogeneous landscape (especially the palaeo-river system) in shaping the genetic diversity of D. orientalis. It enhances our understanding of the evolutionary trends and genetic structure of species in southwestern China and underscores the need for conservation strategies to protect these valuable genetic resources.

This study presents a high-resolution, multiproxy (carbon and oxygen isotopes, trace elements, and strontium isotopes) speleothem record from the Kurdistan Region of Iraq extending from the end of the Last Glacial Maximum (LGM) to the Early Holocene (18.0 to 7.5 ka), encompassing the Epipaleolithic-Neolithic transition in the core area of the Fertile Crescent (FC). The record shows that changes in local rainfall amount were coincident with changes in Greenland temperatures, with increased precipitation and enhanced multidecadal hydroclimatic variability during the Bølling-Allerød chronozone, followed by a drier and dustier Younger Dryas. Comparison with regional paleoclimate data suggests similar precipitation patterns across the FC, but with greater hydroclimate variability during the BA and drier conditions during the YD in the eastern sector. Crucially, the record provides a detailed and well-dated paleoenvironmental template by which to contextualize specific cultural events at the subregional scale, as revealed by recent archaeological research on key sites sharing similar environmental settings, allowing to investigate the role of climatic and environmental changes in shaping different neolithization patterns across the FC.

A significant modulation and adaptive response are observed in Globorotalia menardii from the Bay of Bengal (BoB), reflecting its sensitivity to critical and environmentally stressful conditions. The extreme variations in relative abundance indicate a strong influence of temperature and stratification-driven productivity at the regional scale. The size parameters (maximum diameter (D1), intermediate diameter (D2), and keel thickness) of the species reflect its response to climate and ecological changes over the ~3,4000 years BP. Abundance peaks during warm intervals, such as the Bølling–Allerød (B/A), Holocene, and Medieval Warm Period (MWP), and declines during colder phases, including the Last Glacial Maximum (LGM) and Heinrich events, consistent with the species’ thermophilic nature. The size parameters also increase during warm periods, though their variability suggests stronger control by nutrient availability than by temperature alone. Depth-wise morphological patterns reveal robust, symmetrical, and well-developed tests in the younger intervals, contrasting with irregular and underdeveloped forms in the deeper core samples, reflecting ecological stress. Correlation analysis indicates strong positive interrelationships among the test D1, D2 and keel thickness, signifying proportional morphological development, while abundance shows a moderate negative correlation with core depth. These findings demonstrate that both climatic phases and depositional depth regulate the ecological and morphological expressions of G. menardii , underscoring its reliability as a palaeoceanographic proxy for reconstructing past oceanographic variability in the BoB.

Glacial erosion during the Last Glacial Maximum (LGM) has removed much evidence of earlier glaciations and interglacials in the European Alps. At Gröbminger Mitterberg (GM), beneath a blanket of LGM till, a distinctive sediment archive preserves deposits predating the LGM. GM is a flat‐topped hill in the Enns Valley, Styria (Austria), rising ∼200 m above the valley floor between Mesozoic carbonates (north) and crystalline basement units (south). Crystalline bedrock (phyllite, greenschist) is overlain by subglacial, deltaic, fluvial and glaciolacustrine sediments, with soft‐sediment deformation (clastic dykes) and capped by LGM till. Outcrop, borehole, and electrical resistivity tomography data reveal a bedrock surface incised by a channel. The Middle–Late Pleistocene succession begins with the Lower Till, attributed to the Rissian glaciation (MIS 6), which reshaped a fluvially moulded bedrock surface by intense subglacial erosion, including meltwater activity. Above lies the Mitterberg Unit. The up to 100 m thick Dorf (Allo‐)Member comprises delta foresets with slumps, rare dropstones and dead‐ice contact structures, correlated to Termination II (MIS 6) by luminescence ages of 140±20 ka. The 10 m thick Zirting (Allo‐)Member records fluvial deposition. The upper Frankenbichl (Allo‐)Member consists mainly of interbedded lacustrine and deltaic sediments, showing overall aggradation. Luminescence ages of 47±8 ka suggest a lake formed in MIS 3 by a prograding alluvial fan under cold, ice‐free conditions. The lacustrine succession records alternating delta progradation and dam‐burst‐caused regression. Uppermost Frankenbichl glaciolacustrine deposits reflect glacier‐proximal settings marking the onset of Würmian Pleniglacial (MIS2) ice build‐up. The LGM till unconformably overlies the Mitterberg Unit and forms drumlins. Overall, these reconstructions link climate change, erosion and sedimentation in the Enns Valley, providing a framework for modelling Alpine glaciations and intervening greenhouse phases.