The tectonic evolution of the Paleo-Asian Ocean during the Early to Middle Permian remains a key issue in understanding the geodynamic history of the Central Asian Orogenic Belt. To address this, we conducted petrological, whole-rock geochemical, zircon U–Pb geochronological, and Hf isotopic analyses of Early Permian biotite granodiorite and Middle Permian porphyritic granite from the south-central Great Xing’an Range. Zircon U–Pb dating yields ages of 273.2 ± 1.4 Ma and 264.4 ± 1.5 Ma, indicating that these intrusions emplaced during Early and Middle Permian. Geochemical analyses show that the rocks are characterized by high SiO2 and Al2O3 contents, and low MgO and CaO contents and belong to the metaluminous to weakly peraluminous series, typical of I-type granites. The rocks are enriched in light rare earth elements and large-ion lithophile elements (e.g., Rb, Ba, K), but depleted in heavy rare earth elements and high field strength elements (e.g., Nb, Ta, P, Ti), with weakly negative Eu anomalies. The Early Permian pluton exhibits low-Sr and high-Yb characteristics and thus fall in the plagioclase stability field. In contrast, Middle Permian pluton was derived from magmas generated by partial melting under high-pressure conditions and that, underwent crystal fractionation during ascent to the mid-upper crust, ultimately forming low-Sr and low-Yb type granites. All zircon εHf(t) values are positive (+4.84 to +14.87), with the corresponding two-stage Hf model ages ranging from 345 Ma to 980 Ma, indicating that the magmas were predominantly derived from juvenile crustal materials accreted during the Neoproterozoic to Phanerozoic. Considering these results, we propose that the Paleo-Asian Oceanic plate continued to subduct beneath the Songliao–Xilinhot block to the north during the Early to Middle Permian, with intense subduction and crustal thickening occurring in the Middle Permian. This suggests that the south-central segment of the Great Xing’an Range was situated in an active continental marginal setting during the Early-Middle Permian.

Understanding the foliar absorption and translocation of atmospherically deposited nanoplastics (NPs) in crops is critical for food safety, yet species-specific mechanisms remain inadequately understood, hindering accurate risk assessment for edible crops. In this study, the isotopic tracing (2H-labeled polystyrene NPs) was employed to systematically compare NPs uptake in three leafy vegetables: cherry radish, water spinach, and lettuce. Stable isotope analysis revealed species dependent accumulation under foliar spraying of NPs, with the highest levels observed in leaves of cherry radish (5.1 to 216.3 μg/g dw), followed by water spinach and lettuce. NPs were translocated to roots of cherry radish and lettuce but restricted to stems of water spinach. Scanning electron microscopy visualized NPs in stomatal cavities and roots of cherry radish and lettuce, as well as in the nodes of water spinach. Mechanistic studies linked these differences to three factors: leaf structure and vascular architecture affected NP absorption and transport; plant physiological traits regulated NP content in leaves; and transcriptomic data indicated that gene expression related to the abscisic acid-ROS-Ca2+ mediates stomatal closure pathway. Our findings elucidate how NPs are absorbed and translocated across plant species and highlight species-specific responses to atmospheric NP pollution and associated risks.

ABSTRACTWars impose unprecedented environmental damage that has rarely been studied in real time. Domestic dogs are an accessible model species during war times, because they enable data collection without specialised equipment and skills, which can be performed without creating additional danger to humans or animals involved. We compared phenotypic traits in Ukrainian dogs living close to the front line with those from other regions of Ukraine. We found significant differences in frequencies and diversity of multiple morphological traits, consistent with mortality‐based selection at the front line. We also found differences in age structure and frequency of diseases and injuries, consistent with high mortality of old and ill individuals. The front‐line population had low average BMI and stable isotope analysis suggested malnutrition and low trophic level. Our study shows that wars can be factors of strong and fast natural selection, with the effects comparable to large‐scale natural or anthropogenic disasters.

Abstract In arid and semi-arid regions, protecting groundwater from pollution is essential for public health and sustainable resource management. This study presents a multidisciplinary assessment of shallow aquifer quality, integrating isotopic tracing, statistical analysis, and metal speciation modelling. Eighteen groundwater and surface water samples were analyzed to identify geochemical processes, trace element speciation, and pollution sources. Results from hydrochemical and isotopic analyses indicate that groundwater composition is primarily influenced by water–rock interactions and recharge from the Recent Nile system, with limited recharge from old Nile channels. In addition to some anthropogenic impacts from industrial effluents and agricultural runoff impacts on groundwater quality. Saturation index modeling using PHREEQC revealed oversaturation with carbonate minerals and undersaturation with evaporitic phases. Chemical speciation of trace elements was determined; as it have a direct effect on their mobility and potential toxicity to living organism. Speciation analysis demonstrated that trace element toxicity varies by chemical form; free ionic species such as Cu 2+ and Co 2+ are more bioavailable and pose greater health risks than their complexed counterparts. Groundwater samples contained both aqueous and particulate species, forming complexes with ligands including Cl − , OH − , SO 4 2− , F − , and HCO 3 − . Un-complexed forms of Ba, Mn, Sr, Zn, Co, and Cu were present as free ions, indicating potential for sorption onto aquifer materials. This natural attenuation may limit mobility under low acidity and low organic matter conditions. However, it may not fully mitigate health risks, and artificial treatment could be required depending on contaminant concentrations and exposure scenarios. Graphical abstract

Sustainable water management in regions impacted by artisanal gold mining (ASGM) requires a clear understanding of hydrochemical evolution and salt transformation processes. This study examines hydrochemical changes in the Wadi Abbady through a combined approach of geochemical modeling and stable isotope analysis, with the aim of disentangling the roles of natural processes and human activities in alternating water quality. Physicochemical parameters, major ions, and isotopic signatures were analyzed to trace both natural and anthropogenic influences. Results reveal pronounced chemical evolution within the Nubian Sandstone Aquifer (NSA), primarily controlled by reverse ion exchange. Mining activities induce a hydrogeochemical transformation, converting meteoric surface water assemblages (Ca (HCO3)2-Mg (HCO3)2-NaHCO3-NaCl-Na2SO4) into slightly brackish water characterized by elevated sulfate salt concentrations (NaCl-Na2SO4-CaSO4-MgSO4-Ca (HCO3)2). Isotopic evidence indicate that the Quaternary Aquifer (QA) is not hydraulically connected to the deeper NSA, and is instead predominantly recharged by surface water through Wadi Abbady canals and irrigation return flows. End-Member Mixing Analysis (EMMA) using Cl- and δ18O indicates that irrigation canals contribute approximately 60-90% of the total recharge to the QA, while amalgamation ponds provide a smaller but consistent contribution of 10-40%. This mixing pattern highlights both the hydrogeological connection between surface and shallow groundwater systems and the increased vulnerability of the QA to contamination originating from ASGM activities. These findings advance current understanding of water quality evolution in mining-affected environments and highlight the vulnerability of local aquifer systems to unregulated mining practices. This study emphasizes the need for continuous monitoring and long-term hydrochemical assessment in comparable settings to support sustainable water management and mitigate the impacts of artisanal mining.

ABSTRACTRationaleIn January 2024, the IAEA experts meeting endorsed both δ13C scales that are currently used within the scientific community: the Vienna Peedee belemnite (VPDB) δ13C scale defined by NBS 19 with a value of +1.95‰ exactly, and the VPDB‐LSVEC scale defined by NBS 19 and the lithium carbonate LSVEC with a value of −46.60‰ exactly. Following the discovery of the instability of the LSVEC material, several expert laboratories independently proposed replacement reference materials (RMs). This study compares these calcium carbonate RMs IAEA‐610, ‐611, ‐612, and USGS44 at the highest level of the metrological traceability chain and recommends values that enable users to realize the VPDB and VPDB‐LSVEC scales.MethodsThe phosphoric acid reaction that is required to evolve CO2 from calcium carbonate RMs for isotope analyses is scrutinized by comparing the results of the different apparatuses used in the three participating laboratories. All three laboratories use high‐precision dual‐inlet isotope ratio mass spectrometers and assess the individual instrument offsets in terms of their effects on interlaboratory comparability of samples.ResultsThe reported values for IAEA‐610, ‐611, ‐612, and USGS44 on the δ13CVPDB scale are −9.114 ± 0.011‰, −30.815 ± 0.011‰, −36.739 ± 0.020‰, and −42.073 ± 0.015‰, respectively. Within their measurement uncertainty they are identical to previously published values. Finally, we provide values on the δ13CVPDB and δ13CVPDB‐LSVEC scales for some RMs that are routinely used in elemental analysis–isotope ratio mass spectrometry.

The degree of homogeneity in the diet of archaeological populations associated with Brazilian shellmounds (sambaquis) is an ongoing debate. Isotopic studies have the potential to document both intra- and inter-group dietary variability, especially when paired with quantitative tools, such as Bayesian Mixing Models. In this study, we investigate intra-site variability on diet at two shellmounds in southeastern Brazil: Piaçaguera (7151–5668 yBP), characterized by two distinct burial clusters, and Moraes (6791–5590 yBP). We analyzed δ13C and δ15N on human and fauna bone collagen (n = 43) and on human dentine collagen (n = 5 teeth). Our data were complemented by previously published isotopic data from these sites (n = 88) and from other Brazilian shellmounds (n = 51). To quantify the consumption of different food sources, we adapted the Bayesian MixSIAR model to integrate both bone and dentine values without compromising sample independence. Our results indicate that marine fish contributed approximately 30–50% to the diet of individuals from Piaçaguera, and terrestrial animals accounted for 16–45% of the diet of individuals from Moraes. We observed a slight difference in the consumption of marine and terrestrial sources between the burial groups in Piaçaguera and a higher intake of freshwater fish among subadults in Moraes. New radiocarbon dating in Piaçaguera indicates that the two burial groups did not belong to distinct chronological periods. These findings highlight the importance of a constant dialog between archaeological and isotopic data. The adapted MixSIAR model validated and increased the robustness of our results, proving to be effective in delineating dietary patterns in past groups from distinct archaeological contexts.

Understanding past human and animal mobility is essential for reconstructing the social and cultural dynamics of ancient societies. Strontium isotope analysis (87Sr/86Sr) offers a powerful tool to investigate provenance and movement. The bioavailable 87Sr/86Sr follows the underlying lithology, and increasing efforts have been made to map its spatial distribution across the landscape and produce 87Sr/86Sr isoscapes at local and more global scales. Mongolia’s steppe landscapes have long supported highly mobile pastoralist societies whose movements were central to the formation of major polities, including Late Bronze Age cultures, Xiongnu first nomadic state and Mongol Empire. Despite the growing use of 87Sr/86Sr isotopic analysis to investigate past mobility, the lack of a robust 87Sr/86Sr baseline has hindered large-scale interpretations. Here, we generated a regionally-calibrated bioavailable 87Sr/86Sr isoscape for Mongolia by analysing modern plants collected at 534 sites, mostly from Arkhangai, central Mongolia. We used two machine learning approaches: the random forest regression (RF) and the ensemble machine learning (EML). Both methods produced comparable isoscapes with RF slightly outperforming EML. Three major regions have been identified, reflecting the complex geology of Mongolia: a western intermediate-to-high 87Sr/86Sr region (0.710–0.722), a central low 87Sr/86Sr region (0.707–0.711), and an eastern intermediate 87Sr/86Sr region (0.709–0.712). Comparison of archaeological 87Sr/86Sr data from 25 sites across Mongolia from the Late Bronze Age to the Medieval period with local isoscape predictions suggest that human, animal and plant samples are mainly of local origins for most of the sites, regardless of the period. This isoscape provides a strong baseline in Mongolia and not only enhances archaeological interpretations of past mobility but also holds significant potential for ecological monitoring and the authentication of regional products, such as cashmere.

ABSTRACT Burial in the Italian Bronze Age is often thought to consist mostly of single burials, cremations in necropolises or collective burials in tombs. Multidisciplinary study of Coppa Nevigata (Apulia), an important fortified living and trading site on the Adriatic coast, also provides exceptional evidence for a range of funerary rituals. Combining archaeological context and bioarchaeological analysis with new studies of funerary taphonomy, we trace three core modes of deposition within this habitation site: burial, exposure and intentional secondary deposition of single bones, with evident movement of remains between all funerary contexts. Integrated with new isotopic and aDNA analyses, some differences emerge between these three depositional modes. As a result, we suggest that these diverse deathways were motivated by a range of factors, including the power of bones and ancestors, sentiments of group belonging, and political claims.

Abstract. The Middle to Late Miocene was a time of significant global climate change. In the eastern Mediterranean region, these climatic changes coincided with important tectonic events, which resulted in changes to the organisation of oceanic gateways, altering oceanic circulation patterns. The Miocene Climatic Optimum (MCO) is regarded as the most recent CO2-driven warming event in Earth's climate history and has been proposed as an analogue for future climate change. We present a ca. 12 Ma record of oxygen and carbon stable isotopes from the island of Cyprus to help constrain the nature and extent of Miocene palaeoceanographic changes in the eastern Mediterranean region. Cyprus exposes Neogene deep-sea pelagic sedimentary rocks which are suitable for stable isotope studies. Our composite geochemical record integrates data from the Lower to Upper Miocene succession at Kottaphi Hill along the northern margin of the Troodos ophiolite, with the Upper Miocene succession at Lapatza Hill in the north of Cyprus. Calcareous nannofossil biostratigraphy reveals that the composite record spans the Miocene Climatic Optimum's onset to the beginning of the Messinian Salinity Crisis (MSC). The new stable isotopic record reveals a complex interplay between global climate change and regional to local tectonic changes. In the earlier part of the record, global climate changes dominated; however, by the end of the Late Miocene, tectonic events culminated in isolation of the Mediterranean basins, resulting in a deviation from global open-ocean trends. Strontium (Sr) isotope analysis is used primarily to help constrain the age of the Miocene successions sampled and implies changes in the connectivity of the eastern Mediterranean basins during the Late Miocene. The combined data provide a useful reference for oceanographic changes in the eastern Mediterranean basins during the Miocene, compared to the global oceans.

Fish are key bioindicators for understanding the impacts of human-induced environmental disasters. We assessed trophic ecology and metal accumulation (Fe, Mn, Hg) in the smalland abundant characid Astyanax lacustris in the Doce River basin, following the 2015 mining tailings dam collapse. Stable isotope and metal analyses were conducted in fish from six affected sites and two reference sites. Aquatic invertebrates dominated the diet, except near the dam rupture, where algae predominated, and metal concentrations were highest. Fe and Mn concentrations decreased with fish length, Hg increased with fish nitrogen isotopic composition (δ15N), and only Fe showed clear associations with dietary sources. This study is novel in integrating trophic ecology and metal contamination assessment in a sentinel fish species after a major mining disaster. The findings provide insights for biomonitoring and metal risk assessment in freshwater ecosystems worldwide, and highlight Astyanax lacustris as a powerful sensitive bioindicator, reflecting both contamination legacy and ecological pathways of metal accumulation.

Advancing quantitative NMR for high-precision isotopic analysis with rnmrfit 2.0.

Trophic redundancy within a diverse community of sympatric delphinids in the oligotrophic Caribbean Sea.

Revealing the trophic structure of adult Eriocheir sinensis from ponds and rice fields using stable isotope and fatty acid analysis

The marine environment comprises vast regions without physical barriers to movement, making the understanding of population isolation and the evolution of diversity challenging. This is especially the case for highly mobile marine species. Here we investigate populations of the common bottlenose dolphin (Tursiops truncatus) across the Mediterranean Sea and adjacent North Atlantic using high-resolution genomic markers (RADseq) and stable isotope analyses to better understand the evolution of population structure in this system. High-resolution genomic data and broad geographic sampling revealed patterns of structure not previously identified, and integration with stable isotope data suggests that prey choice varies across this region. Unexpected patterns included genetic and isotopic similarity between the North Atlantic and the region around Sicily (but not including the medially located Gulf of Cádiz and surrounding regions). The regional habitat within and beyond the Mediterranean Sea is structured with ocean frontal systems including thermal and halocline transitions, several of which show alignment with genetic transitions within our data. Our data help to distinguish among possible drivers of population differentiation for a marine predator that has the potential for long-distance dispersion.

Adaptations of Xenograpsus testudinatus to shallow hydrothermal vent environments in the western Pacific: A comprehensive review.

Physiological impact of air quality in urban gulls and its implications for their use as pollution sentinels in coastal cities.

Docosahexaenoic acid (DHA), a long-chain omega-3 fatty acid (n3-LCPUFA), is an integral component of vertebrate brains. Vertebrates maintain their DHA levels through biosynthesis using alpha-linolenic acid (ALA; omega-3 precursor) or by consuming preformed DHA and other n3-LCPUFAs which abound in the natural diets of marine predators. Yet, numerous marine predators, including generalist seabirds, now exploit anthropogenic resources potentially deficient in n3-LCPUFAs. Whether they can offset such deficiency by bioconverting ALA into DHA remains unknown. Here, we tested whether chicks of the ring-billed gull (Larus delawarensis), a generalist seabird thriving in cities, can biosynthesize n3-LCPUFAs, including DHA, from ALA. We brought into captivity 12 hatchlings from an urban colony and 12 from a natural colony. Nine hatchlings per colony were gavaged 490 μl of ALA-rich flaxseed oil daily for 3days. The control groups (N=3 urban hatchlings, 3 natural hatchlings) received an omega-3-free caloric equivalent in place of the ALA supplement. All chicks received an omega-3-free diet throughout captivity (72 h). We also attempted to follow ALA's potential bioconversion into n3-LCPUFAs using an oral 13C1-enriched ALA tracer. Unfortunately, compound-specific isotope analyses of brain and liver tissue failed to detect any 13C enrichment. Nevertheless, the flaxseed oil supplementation study provided evidence of some ALA bioconversion. Compared with controls, supplemented chicks from both colonies accumulated more of all ALA derivates in their tissues except for DHA. We demonstrate for the first time that a seabird shows incomplete omega-3 bioconversion abilities, leaving them potentially vulnerable to deficiencies associated with urban foraging and shifting marine ecosystems.

In situ compositional and sulfur isotopic analyses of banded sphalerite from the Kangjiawan Pb-Zn deposit, South China: Insights into incorporation mechanisms of critical metals (Cd, Ga, In)

Nutritional modes in mature orchids range from complete autotrophy to full mycoheterotrophy. Within the genus Cymbidium, interspecific variation in the degree of mycoheterotrophy has been documented, yet intraspecific variation remains poorly understood. Intriguingly, some green Cymbidium species often possess mycorhizomes (coralloid rhizomes), structures commonly found in fully mycoheterotrophic orchids, and morphologically similar to fully mycoheterotrophic seedlings (protocorms). This study examines Cymbidium kanran individuals with and without mycorhizomes to assess whether these specialized subterranean structures enhance fungal carbon acquisition through the use of stable isotope analyses (δ13C and δ15N) and high-throughput metabarcoding techniques. Cymbidium kanran with mycorhizomes exhibit significantly elevated δ13C and δ15N compared to autotrophic reference species and congeneric individuals lacking mycorhizomes. The mycorhizome-bearing plants are partially mycoheterotrophic, obtaining nearly half of their carbon from fungi. The degree of mycoheterotrophy is similar to that of other partially mycoheterotrophic Cymbidium species, such as C. lancifolium and C. goeringii. Fungal communityprofiling revealed that mycorhizome-bearing C.kanran individuals mostly associate with ectomycorrhizal fungi, such as Sebacinaceae, whereas individuals lacking mycorhizomes primarily recruit non-ectomycorrhizal rhizoctonia fungi. Notably, this morphological and nutritional plasticity parallels patterns observed in other orchid lineages, such as Cremastra and Oreorchis, which associate with wood-decay fungi. The findings strongly suggest that persistent protocorm-like mycorhizomes enhance fungal carbon uptake in partially mycoheterotrophic orchids associated not only with wood-decaying fungi but also with ectomycorrhizal fungi. These insights expand understanding of orchid nutritional strategies and highlight how intraspecific morphological plasticity may contribute to the evolution of mycoheterotrophy.