The geomagnetic field is a fundamental component of Earth’s system, shielding the biosphere from solar and cosmic radiation, modulating atmospheric processes, and influencing evolutionary pathways. Its temporal and spatial variability throughout Earth's history may have profoundly shaped the Earth’s habitability and the biosphere. Understanding these linkages is crucial not only for reconstructing past Earth systems but also for assessing planetary habitability beyond Earth.
We welcome contributions on: (i) the behavior and dynamics of Earth’s ancient and present magnetic field and its environmental consequences, including changes in radiation, atmospheric chemistry, and climate; (ii) the influence of Earth’s magnetic field on prebiotic chemistry and the origin of life; (iii) biological responses to magnetic fields in microorganisms, animals and ecosystems, including potential roles in Phanerozoic mass extinctions and evolutionary radiations; (iv) methodological and theoretical advances in magnetic measurements, with emphasis on innovations for detecting weak magnetic signals and biominerals; and (v) applications of biogenic magnetic nanoparticles in Earth science and beyond.
This session will bring together researchers from earth sciences, biology, environmental sciences, and planetary science to exchange ideas and foster interdisciplinary collaboration. It will provide a platform to strengthen biogeomagnetism research and to explore its implications for planetary habitability.
Orals: Tue, 5 May, 08:30–10:15 | Room 2.17
Sedimentary paleomagnetic records provide valuable insights into the behavior of Earth’s magnetic field on millennial to multi-millennial timescales. Directional scatter produced by paleosecular variation (PSV) tends to be elongated along the north–south axis of the magnetic meridian, and the magnitude of this effect depends on site latitude. In contrast, inclination shallowing generates an elongation that is oriented east–west, perpendicular to the magnetic meridian. One of the major issues in the PSV studies is whether such archives have undergone inclination flattening, caused by sediment compaction, which distorts the primary direction of remanence. Moreover, it is necessary to distinguish the non-dipole component of the geomagnetic field with inclination shallowing in the recording signal.
To address this, we applied the recently developed SVEI method (based on the THG24 model) to examine 82 lacustrine and marine records spanning the past 100 kyr for inclination flattening, and found evidence in only one case. However, the traditional E/I approach, based on the TK03.GAD, suggests flattening at 27 mid-latitude sites. When correction inclinations were utilized to construct the model, the comparison result reveals that octupole terms were most affected, underscoring the sensitivity of these higher-order components to inclination flattening. The THG24 model extends beyond the geocentric axial dipole (GAD) representation, employed in TK03.GAD, by incorporating additional axial quadrupole and octupole contributions to the geomagnetic field. This implies that mid-latitude “flattening” signals are non‑dipole contributions rather than by compaction, highlighting that the non-dipole features remain a significant component of the geomagnetic field over the past 100 kyr.
How to cite: Liu, P., Panovska, S., Zhang, K., and Hirt, A.: Non-dipole features of the geomagnetic field on the 100 kyr timescale, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-6920, https://doi.org/10.5194/egusphere-egu26-6920, 2026.
High-resolution geomagnetic record at the end Permian is essential for probing the Earth’s core dynamics, stratigraphic dating, correlation of continental strata with marine ones, as well as linkage between biosphere variation and geomagnetic field. Here, we report a high-resolution geomagnetic polarity sequence across the Permian Guadalupian-Lopingian boundary (GLB, ~260 million year) from South China. This record reveals an episode of exceptionally high polarity reversal rate. Notably, fluctuations in the geomagnetic polarity reversal coincide with major global changes - including Pangea configuration shift, widespread volcanism, and Paleozoic sea-level lowstand and biodiversity perturbations. Cross-correlations indicate that moderate environmental stress may enhance biodiversity, whereas exceeding tolerance thresholds drives the biodiversity declines and potential extinction events. These findings highlight that geodynamic forcing as an essential control on the long-term stability and habitability of biosphere.
How to cite: Zhang, M., Qin, H., Deng, C., Shen, S., Zhu, R., and Pan, Y.: Anomalous high geomagnetic reversal frequency at the end-Permian, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-3227, https://doi.org/10.5194/egusphere-egu26-3227, 2026.
Magnetotactic bacteria (MTB) are a unique group of microorganisms that biomineralize membrane-bound magnetic nanoparticles, termed magnetosomes. These magnetosomes are generally arranged into chains, enabling MTB to sense and navigate along the geomagnetic field lines and efficiently locate their preferred living zone, most commonly the oxic–anoxic transition zone (OATZ). MTB show remarkable morphological and taxonomic diversity and are widely distributed in freshwater, marine, and extreme environments, where they play important roles in the cycling of Fe, C, P, S. However, the in situ niches and spatiotemporal distribution patterns of different MTB lineages remain poorly understood. In this study, MTB cells were first isolated and enriched from a freshwater lake in Beijing, China, and then cultivated under simulated OATZ conditions in glass tubes. Transmission electron microscopy (TEM) observations revealed three representative MTB lineages: magnetotactic cocci (belonging to the class Magnetococcia) producing prismatic-shaped magnetite, magnetotactic spirilla (Alphaproteobacteria) forming cuboctahedral-shaped magnetite, and magnetotactic curved-rods (Desulfovibrionia) producing bullet-shaped crystals. During incubation, the initially formed microbial band in the OATZ developed a clear vertical stratification, with microaerobic conditions in the upper and middle layers and anaerobic conditions in the lower layer. TEM observations and metagenomic quantification demonstrated that magnetotactic cocci dominated the upper layer, magnetotactic spirilla were most abundant in the middle layer, and magnetotactic curved-rods were largely confined to the lower layer. Finally, metabolic reconstruction based on genomic data indicates that differences in oxygen-related metabolic pathways may be responsible for this vertical segregation. Collectively, our results demonstrate oxygen-driven niche partitioning among MTB lineages within the OATZ, highlighting their distinct metabolic adaptations and ecological roles.
How to cite: Wan, J., Zheng, J., Ji, R., Yu, S., Zhu, R., and Lin, W.: Stratified niche partitioning of magnetotactic bacteria near a simulated oxic–anoxic transition zone, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8883, https://doi.org/10.5194/egusphere-egu26-8883, 2026.
Magnetofossils are potential recorder of paleoenvironmental conditions that control the abundance and diversity of magnetotactic bacteria and giant iron biomineralizing organisms in marine sediments. In this study, we conducted suite of rock magnetic and transmission electron microscope analyses on marine (modern, fossil) sediments deposited during different climatic events to characterize the magnetofossil contribution and establish the magnetofossil records in the diverse regions of the northern Indian Ocean. First-order reversal curve diagrams of the representative samples confirmed the presence of non-interacting single domain magnetofossils. High-resolution electron microscope observations results indicate that conventional and giant type magnetofossils are more abundant, widespread, and spatially distributed within northern Indian Ocean. Electron diffraction and energy dispersive spectrometry confirmed their distinctive morphologies and magnetite crystal structure. Magnetic hysteresis and isothermal remanent magnetization curves, first-order reversal curve diagrams, and low-temperature magnetic measurements revealed large variations in magnetic properties of magnetofossils (conventional and giant), which mainly relate to the specific region, climatic events, and time periods. Our findings on the existence of conventional and giant magnetofossils, their abundance, morphological signatures and bulk magnetic measurements expands our understanding of modern and paleoenvironmental conditions (oxygenation, productivity, weathering and sedimentation patterns, nutrient supply, `influx of reactive iron, organic carbon content) that controlled the growth and preservation of magnetofossils in the modern and ancient sediments in the northern Indian Ocean.
How to cite: Badesab, F., Kadam, N., and Sagavekar, O.: Magnetofossils in the Northern Indian Ocean, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16582, https://doi.org/10.5194/egusphere-egu26-16582, 2026.
Biogenic magnetite nanoparticles produced by microorganisms are ubiquitous in modern environments and are also thought to be abundant in ancient sediments such as banded iron formations and paleosols, given the early emergence of iron-metabolizing microbes. Magnetite can form intracellularly within magnetotactic bacteria (MTB) or extracellularly through dissimilatory iron-reducing bacteria (DIRB). While MTB-derived magnetite exhibits distinctive morphological, chemical, and magnetic biosignatures, identifying DIRB-produced magnetite in ancient sediments remains challenging because its nanometer-sized, aggregated, and often superparamagnetic nature overlaps strongly with abiotic magnetite. In this study, we systematically investigate the behavior of 21 trace elements in biogenic magnetite and abiotic magnetite formed via the transformation of ferrihydrite substrates coprecipitated with different trace-element concentrations. Biogenic magnetite was produced by the DIRB Shewanella oneidensis MR-1, while abiotic magnetite was generated using dissolved Fe²⁺ under comparable conditions. Notably, biogenic magnetite particles were consistently smaller than their abiotic counterparts under same conditions, suggesting that microbial processes impose additional constraints on crystal growth. Additionally, ICP-MS results reveal that most trace elements are preferentially enriched in abiotic magnetite, whereas cobalt (Co) and cadmium (Cd) are consistently enriched in biogenic magnetite, independent of initial trace-element concentrations or washing treatment. In contrast, magnesium (Mg) shows preferential incorporation into abiotic magnetite. The observed differences in trace-element signatures, particularly Co–Cd enrichment in biogenic magnetite and Mg enrichment in abiotic magnetite, provide a promising geochemical indicator for identifying DIRB activity in ancient iron-rich sediments and reconstructing microbial iron cycling in early oceans.
How to cite: Han, X., Lin, W., and Pan, Y.: Trace Element Partitioning as a Geochemical Biosignature of Biogenic Magnetite Formed by Iron-Reducing Bacteria, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8690, https://doi.org/10.5194/egusphere-egu26-8690, 2026.
Peptide synthesis in modern biology proceeds via aminoacyl adenylates (5′-aa-AMP), which are central to both peptide bond formation and chiral recognition. Inspired by this mechanism, our previous work showed that amino acids, adenosine, and trimetaphosphate can spontaneously form N-aminoacyl adenylates (N-aa-AMP) under aqueous conditions, suggesting N-aa-AMP as a plausible prebiotic precursor of 5′-aa-AMP. Importantly, N-aa-AMP formation exhibits intrinsic chiral selectivity, with L-amino acids preferentially pairing with D-nucleosides and vice versa, raising the question of whether such selectivity persists during peptide synthesis.
We previously investigated peptide formation between N-Phe-F-AMP and racemic amino acids at pH 9 and 37 °C. N-L-Phe-F-AMP preferentially reacts with L-amino acids, promoting homochiral dipeptide formation, while N-D-Phe-F-AMP shows the corresponding mirror selectivity. This behavior is consistent across several amino acids (Ile, Leu, Ala, Val, and Pro), with homochiral excesses ranging from 12.04% to 67.84%, demonstrating that N-aa-AMP intrinsically directs chiral selection during peptide formation. Here, we investigated the effect of magnetic fields on this process. Compared with moderate magnetic fields (MMF), geomagnetic (GMF) and hypo-magnetic (HMF) conditions significantly enhance chiral selectivity, with the strongest amplification observed under HMF. These results suggest that the weak magnetic environment of early Earth may have influenced reaction dynamics and intermolecular interactions, thereby facilitating chiral amplification during prebiotic peptide synthesis.
Overall, our findings indicate that N-aa-AMP can promote homochiral peptide formation under enzyme-free and metal-free prebiotic conditions, while magnetic fields may serve as an additional physical factor modulating chiral selection. This work introduces magnetic effects into prebiotic reaction networks and provides new insights into the emergence of biological homochirality.
How to cite: Zhang, M., Zheng, X., Chen, J., Xie, S., Zhao, Y., and Ying, J.: Magnetic Field Effects on Chiral Selection in Peptide Formation Mediated by N-aa-AMP, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8908, https://doi.org/10.5194/egusphere-egu26-8908, 2026.
The search for extraterrestrial life requires rigorous criteria to distinguish between abiotic chemical networks and authentic biosignatures. The evolution of complex macromolecules from simple precursors is a pivotal event in the origin of life. Pathways such as the Strecker synthesis and cyanate polymerization reactions elucidate the availability of building blocks. The role of the geomagnetic field (GMF) in shaping prebiotic chemical evolution has mainly remained underexplored. Here, we investigate the GMF as a potential regulator of the urea-mediated N-carbamoylation of amino acids, a crucial thermodynamic pathway for the formation of prebiotic peptides.
By simulating primordial planetary conditions, we systematically evaluated the reaction efficiency of all proteinogenic amino acids under GMF (~50 µT) and hypo-magnetic field (HMF, <20 nT) conditions. The yield of CAA production from most amino acids (14/20) is significantly higher under GMF. These results revealed a nuanced landscape of magnetic sensitivity. While statistically significant yield variations were observed between GMF and HMF environments, no uniform directional trend was evident across the amino acid spectrum. Instead, magnetic field effects were heterogeneous and contingent on specific side-chain characteristics.
These findings suggest that the GMF functions not as a dominant driver but as a subtle modulator of prebiotic synthesis. We hypothesize that the GMF likely influenced the distribution of early peptides, acting as an auxiliary variable that contributes to the complexity of prebiotic chemical evolution on Earth and potentially habitable exoplanets.
How to cite: Chen, F., Zheng, X., Yu, S., Xie, S., Zhao, Y., and Ying, J.: Geomagnetic Field Modulation of Prebiotic N-Carbamoylation, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8909, https://doi.org/10.5194/egusphere-egu26-8909, 2026.
The geomagnetic field (GMF), as one of Earth’s fundamental environmental physical fields, remains underexplored in terms of its potential regulatory role in prebiotic chemical processes. Investigating its influence on key chemical reactions related to the origin of life can help elucidate how early Earth conditions shaped the formation and evolution of primordial biomolecules. ATP, as a central energy currency, undergoes non-enzymatic hydrolysis that is crucial for early energy metabolism, and the synergistic effects of metal ions and simple molecules such as amino acids may serve as important drivers of this process. This study focuses on the regulatory effect of the GMF on the metal–amino acid cooperative catalysis of ATP hydrolysis.
Integrating bioinformatics analysis with chemical experiments simulating primitive planetary conditions, we systematically investigated the synergistic effects of Mg2+, Mn2+, and Ca2+ combined with representative amino acids on ATP hydrolysis under different magnetic field environments. The results indicate that metal ion together with acidic/polar amino acids (e.g., Asp, Thr) can significantly accelerate ATP hydrolysis under a hypomagnetic field (HMF) compared to the contemporary GMF environment. Further mechanistic studies suggest that this process may be associated with a metal-dependent radical pathway.
These findings imply that the GMF may act as a subtle modulator, influencing the chemical behavior of metal ions and radical reaction pathways, thereby participating in the regulation of early ATP hydrolysis and related energy metabolism networks. This research provides a new experimental perspective and chemical model for understanding the potential role of the GMF in prebiotic chemical environments, and also offers new criteria for assessing potential pathways of chemical evolution toward life on other planets.
How to cite: Xu, C., Shi, Y., Guo, Y., Zhao, Y., and Fu, S.: The Role of the Geomagnetic Field in ATP Hydrolysis under Prebiotic Earth Conditions, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-20833, https://doi.org/10.5194/egusphere-egu26-20833, 2026.
The geomagnetic field (GMF) is a pervasive yet poorly understood environmental factor for plant growth and development. Here, we reveal that near-zero magnetic field (NZMF) significantly delays seed germination in Arabidopsis thaliana. Time-resolved transcriptomic analyses showed a subtle but coordinated transcriptional shift under NZMF, characterized by downregulation of growth-promoting genes and upregulation of defense-related pathways. This transcriptional reprogramming coincided with moderate accumulation of reactive oxygen species (ROS), linking redox signaling to the germination delay. Consistently, scavenging ROS partially restored germination rates and reversed differential expression of a subset of stress-responsive genes, confirming the central role of ROS in the NZMF-induced transcriptional reprogramming. Genetic analysis using cry1cry2 mutants further indicated that NZMF delays seed germination via both CRY-dependent and -independent pathways. Taken together, our findings suggest that the GMF acts as an environmental cue that fine tunes the balance between growth and defense during plant early development, likely through a redox-dependent mechanism underlying plant responses to magnetic field perturbations. These results provide a possible mechanistic insights into how paleomagnetic variations may have imposed selective pressures on the biosphere and offer a framework for assessing plant habitability in extraterrestrial environments with weak magnetic fields.
How to cite: Xu, X. and Huang, J.: Near-zero magnetic field inhibits seed germination via ROS signaling and reprogramming transcriptome in Arabidopsis thaliana, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-22850, https://doi.org/10.5194/egusphere-egu26-22850, 2026.
The detection and interpretation of brain magnetic signals are crucial for biomagnetism and advancing brain-computer interface (BCI) technologies. Local field potential (LFP) signals, reflecting synchronized neuronal ensemble activity, offer insights into coordinated neural function. Due to their compact size and exceptional sensitivity at room temperature, magnetoresistance (MR) sensors have garnered considerable interest in numerous fields, particularly in the detection of weak magnetic signals in biological systems. The “magnetrodes”, integrating MR sensors with needle-shaped Si-based substrates, are designed to be inserted into the brain for local magnetic field detection. In this study, we develop a miniaturized tunneling magnetoresistance (TMR)-based neural magnetrode optimized for in vivo LFP magnetic recording. The magnetrode achieves a magnetoresistance ratio (145%) and low-field sensitivity (16.59 mT/%), while maintaining low detection limits of 4.8 nT/√Hz at 1 Hz and 140 pT/√Hz at 1 kHz. Noise analysis revealed that reducing bias current and applying high-frequency AC excitation significantly suppresses low-frequency 1/f noise. In vitro simulations validate LFP reconstruction capability, and in vivo experiments demonstrate a strong correlation (r = 0.857 ± 0.031, p < 0.01) between magnetic and electrical LFPs. Furthermore, in vitro durability tests in artificial cerebrospinal fluid demonstrated exceptional stability, with negligible signal drift (< 0.4% variation in TMR ratio) over a 7-day period. This work establishes that the TMR-based magnetrode emerges as a new potential tool for neural interface technologies, with implications for real-time BCI and neuropathology research.
How to cite: Chen, J., Wang, Y., Xu, Z., Luo, J., Zhang, C., Jin, Z., Wang, M., and Cai, X.: Advanced TMR Sensor-Based Magnetrodes for High-Sensitivity Biomagnetic Field Detection, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-22550, https://doi.org/10.5194/egusphere-egu26-22550, 2026.
The geomagnetic field (GMF) and life both emerged in the early Earth and have co-evolved to the present day. The spatial and temporal variations of the GMF have profoundly influenced the environment and biosphere. The NSFC’s Outstanding Research Group Project "The Geomagnetic Field and Life" is dedicated to exploring this fundamental relationship through interdisciplinary research. We bring together leading experts from China in Earth sciences, biology, chemistry, and information science. Our integrated approach focuses on developing high-sensitivity magnetic instrumentation to conduct systematic, multi-scale studies. Core research objectives include: 1) correlating spatiotemporal geomagnetic variations with major events in the history of life, 2) characterizing changes in the palaeomagnetic field, 3) investigating the biological effects of magnetic fields, and 4) elucidating the cellular and molecular mechanisms of magnetoreception. This project aims to establish a theoretical framework for understanding how geomagnetic field variations have shaped Earth's habitable conditions and the evolution of life. It also seeks to advance applications of biomagnetic effects and biogenic magnetic nanomaterials. Ultimately, this project will provide new insights into the co-evolution of life and the geomagnetic environment.
How to cite: Pan, Y., Zhao, Y., Wei, Y., Li, J., Lin, W., Yu, S., and Zhu, R.: A NSFC Project: The Geomagnetic Field and Life, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16252, https://doi.org/10.5194/egusphere-egu26-16252, 2026.
We present a physics-informed neural network (PINN) framework for geomagnetic data assimilation, aimed at reconstructing the time-dependent state of the Earth’s outer core, consistent with both geomagnetic observations and the governing equations of the geodynamo. The method incorporates the quasi-geostrophic magneto–Archimedean–Coriolis (QG–MAC) balance, together with the magnetic induction and thermal diffusion equations, as embedded physical constraints within the neural network training. Flow, magnetic, and temperature fields are represented using a poloidal–toroidal spectral decomposition, enabling an efficient description of large-scale core dynamics in a rotating spherical shell.
Synthetic assimilation experiments based on benchmark dynamo models demonstrate that the proposed framework can successfully recover the temporal evolution of the core state from magnetic field observations, with the reconstructed flow and magnetic fields reproducing the main characteristics of the reference solutions. The results further indicate that the method is capable of recovering small-scale magnetic field features at the core–mantle boundary. The framework is subsequently applied to geomagnetic data assimilation using observations from the COV-OBS geomagnetic field model. Using approximately 180 years of historical geomagnetic observations, we reconstruct the structure of the Earth’s core state and perform short-term (20 years) predictions of the magnetic field evolution.
How to cite: Li, J. and Zhang, K.: Physics-informed neural networks for geomagnetic data assimilation, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7291, https://doi.org/10.5194/egusphere-egu26-7291, 2026.
Amino acids serve as the fundamental building blocks of proteins and perform indispensable biological functions in living systems. During chemical evolution, α-amino acids played a crucial role as key structural modules in the assembly of primitive proteins and the formation of early metabolic networks. However, why life selected α-amino acids, rather than other structural types of amino acids, as the core components of protein backbones remains a fundamental question in origins-of-life research: Is this a result of life systems screening a pre-existing molecular library in the prebiotic environment, or does it stem from the unique physicochemical properties and reaction kinetics advantages of α-amino acids? Phosphorus, an essential element constituting nucleic acid backbones and participating in cellular energy metabolism, may have profoundly influenced this selection process through phosphorylation reactions driven under prebiotic chemical conditions.
This study utilized magnetic circular dichroism (MCD) spectroscopy to systematically compare the spectral behaviors of N-phosphorylated α-, β-, and γ-alanines in an aqueous environment. The results revealed that only the α-phosphorylated alanine exhibited a characteristic MCD signal under a magnetic field, which is attributed to a high-energy intermediate formed via an intramolecular five-membered ring transition state. Further experiments demonstrated that under a relatively strong external magnetic field, the rates of prebiotic reactions involving N-phosphorylalanine, such as hydrolysis and peptide bond formation, were significantly enhanced .
Based on these findings, we propose that magnetic fields can modulate the spatial orientation of functional groups within phosphorylated amino acid molecules, effectively stabilizing key reaction intermediates and reducing the reaction energy barrier. This mechanism provides important experimental evidence for understanding how life specifically selected the phosphorus metabolic pathway and α-amino acids in the early Earth environment. It also reveals, from a physicochemical perspective, that the selection of biochemical molecular structures may originate from their intrinsic properties and their reactivity adaptability within the Earth's magnetic field.
How to cite: Zhang, C., Showkat Ahmad, B., Zhao, Y., and Zhao, H.: MCD Reveals a Magnetic Field-Sensitive Pathway for Life’s Choice of α-Amino Acids, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-18096, https://doi.org/10.5194/egusphere-egu26-18096, 2026.
Magnetotactic bacteria (MTB) are microorganisms that navigate Earth's geomagnetic field by biomineralizing intracellular, membrane-bound nanocrystals of magnetite (Fe3O4) and/or greigite (Fe3S4), known as magnetosomes. These bacteria are important models for studying magnetoreception and biomineralization, with broad implications for astrobiology, paleoenvironmental reconstruction, sedimentary magnetism, and biomedical applications. Although, MTB have been identified across at least 16 bacterial phyla, their study has been hampered by challenges in cultivation. Genome-resolved metagenomics has thus become essential for elucidating their metabolic diversity, ecological adaptations, and evolutionary history. Despite the rapid accumulation of MTB genomes, these data are scattered across different databases, often with inconsistent quality assessments and incomplete metadata, which hinder comprehensive comparative and interdisciplinary analyses.
To address this, we developed the Genomic Database of Magnetotactic Bacteria (GdbMTB, https://www.gdbmtb.cn/), a curated genomic resource dedicated to MTB research. GdbMTB integrates publicly available MTB genomes and associated metadata, and applies a standardized bioinformatics workflow to provide uniform quality assessment, taxonomic classification, and annotations of magnetosome-related genes. Each genome is accompanied by environmental and publication metadata, offering context and traceability to original studies. With an interactive, user-friendly interface and direct links to external genomic databases, GdbMTB facilitates intuitive data exploration and cross-database navigation.
By consolidating high-quality MTB genomic resources with comprehensive metadata, GdbMTB establishes a foundation for large-scale, interdisciplinary studies on the ecology, evolution, and environmental significance of magnetotactic bacteria.
How to cite: Ji, R., Pan, Y., and Lin, W.: GdbMTB: A Curated Genomic Database of Magnetotactic Bacteria, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11432, https://doi.org/10.5194/egusphere-egu26-11432, 2026.
Plate tectonics is central to the long-term release of heat from Earth’s deep interior, which ultimately maintains habitability, as well as nutrient cycling on the surface important for evolution. A strong magnetic field can further assist evolution by shielding life from harmful cosmic radiation. Paleomagnetic data indicate a strong magnetic field in the Late Paleoarchean through the Proterozoic (Tarduno et al., Nat Sci Rev, 2025), but the onset of plate tectonics has been unclear. Recent paleomagnetic analyses indicate that rocks from the Pilbara craton, once thought to record early plate tectonic motion, have been magnetically reset. Instead, paleomagnetic analyses indicate a Neoarchean start for latitudinal motions similar to modern plate tectonics. This late start of plate tectonics coincides with the evolution of PMI and PMII photosystems and crown group cyanobacteria. Increased nutrient cycling and sedimentary basin environments associated with a Neoarchean onset of plate tectonics, together with robust magnetic shielding provided by a strong magnetic field, may have aided cyanobacteria evolution, accelerating oxygenation of the atmosphere.
How to cite: Cottrell, R. D. and Tarduno, J. A.: Robust magnetic shielding and the onset of plate tectonics assisted Neoarchean evolution, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-22536, https://doi.org/10.5194/egusphere-egu26-22536, 2026.
The South Atlantic Anomaly (SAA), characterized by a significantly weakened geomagnetic field, provides a unique natural laboratory to study the biological and ecological consequences of altered magnetic shielding. This region exhibits a large magnetic potential gradient between its central depression (where surface intensity can be 47.8% weaker than the global average according to the CHAOS-8.2 model). Following geomagnetic storms, the SAA experiences enhanced particle precipitation, leading to pronounced atmospheric disturbances. These include prolonged ozone depletion and potential impacts on cloud microphysics and regional climate patterns. Furthermore, the anomalous magnetic environment may directly affect biology by disrupting magnetoreception in migratory species and influencing physiological processes. This synthesis highlights the critical interplay between geomagnetic activity, the distinct magnetic landscape of the SAA, and its multifaceted effects on ecosystems, offering insights into planetary habitability under evolving magnetic conditions.
How to cite: Shen, J., Yue, Y., Rong, Z., Lin, W., Wei, Y., and Pan, Y.: Possible biological effects of geomagnetic perturbations in the South Atlantic Anomaly, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7258, https://doi.org/10.5194/egusphere-egu26-7258, 2026.
Accumulating evidence has shown that exposure to an extremely low magnetic field (hypomagnetic field, HMF, <5 µT) for extended periods has detrimental effects on the function of multiple systems in animals. In the adult mammalian brain, neural stem cells are present in the subventriclular zone and the dentate gyrus. These cells continually generate new neurons, which support learning and memory. This process of adult neurogenesis is highly sensitive to external environmental stimuli. We have experimentally revealed that, after long-term exposure to HMF, mice showed defective adult neurogenesis and cognitive dysfunction. Mechanistically, HMF exposure directly inhibits adult neurogenesis by suppressing mitochondrial oxidative phosphorylation and reducing the levels of endogenous reactive oxygen species (ROS) in neural stem cells. Additionally, HMF exposure increases the global ROS levels in the hippocampus. This ROS increase triggers oxidative stress and activates downstream inflammatory pathways, ultimately leading to chronic neuroinflammation. These findings indicate the essential role of the ambient geomagnetic field (GMF) in maintaining adult neurogenesis and cognitive function in mice and provide valuable hints for assessing the potential risks extremely weak magnetic field exposure in future manned deep-space missions.
How to cite: Ren, J., Luo, Y., Zhang, B., Tian, L., Guo, W., and Pan, Y.: The Effects of Extremely Low Geomagnetic Field Intensity on the Mammalian Central Nervous System, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15577, https://doi.org/10.5194/egusphere-egu26-15577, 2026.
How to cite: Winklhofer, M., Höfken, A. F., von Dobeneck, T., Kuhn, T., and Kasten, S.: Deep-living magnetotactic bacteria in hydrothermally bottom-up oxygenated sediments: a case for a mirror world, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-22579, https://doi.org/10.5194/egusphere-egu26-22579, 2026.
Posters virtual: Thu, 7 May, 14:00–18:00 | vPoster spot 2
EGU26-8273 | ECS | Posters virtual | VPS6
Magnetic Disturbances to Cetaceans in IsafjörðurdjupThu, 07 May, 14:21–14:24 (CEST) vPoster spot 2
Evidence suggests cetaceans utilise magnetoreception to navigate using magnetic fields. However, disturbances in the geomagnetic field from solar storms and anthropogenic activity can lead to beachings. Previous studies indicate fluctuations around 50 nT are large enough to influence strandings. Ísafjarðardjúp is home to a large humpback whale population in the summer, but marine activity, including fish farms, vessel traffic and coastal structures such as the Bolafjall radar station, makes the fjord prone to magnetic interference, potentially intefering with magnetoreception.
How to cite: Rahman, A.: Magnetic Disturbances to Cetaceans in Isafjörðurdjup, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8273, https://doi.org/10.5194/egusphere-egu26-8273, 2026.
EGU26-17838 | ECS | Posters virtual | VPS6
Research progress on magnetotactic bacteria under high magnetic fieldThu, 07 May, 14:24–14:27 (CEST) vPoster spot 2
Magnetotactic bacteria (MTB) are an ancient microbial lineage that navigate geomagnetic field lines via intracellular magnetosomes, and their unique multi-disciplinary properties have long drawn research attention. This study focuses on MTB’s behavioral and metabolic adaptations under high magnetic fields—including extreme environments six orders of magnitude stronger than the geomagnetic field—and explores their application potential.Our recent progress is outlined as follows: 1) Using Magnetospirillum gryphiswaldense MSR-1 as the model strain, we analyzed how high magnetic fields reprogram MTB metabolism, modulate biomineralization dynamics, and impact MmaK scaffold assembly as well as magnetofossil genesis.2) We clarified the regulatory role of MTB-derived Mms6 protein in biomineralization, and synthesized magnetosome-mimetic nanocrystals in vitro that match natural magnetosomes in cuboctahedral morphology, soft ferromagnetic behavior, and high saturation magnetization. 3) We built a magnetic nanorobot-based navigation system to realize precise spatial control and trajectory planning of MTB, paving new ways for MTB-mediated nanodrug delivery and magnetic navigation.
References
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How to cite: Wang, J. and Ma, K.: Research progress on magnetotactic bacteria under high magnetic field, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-17838, https://doi.org/10.5194/egusphere-egu26-17838, 2026.
