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Harnessing traits to predict economic impacts from biological invasions
No full textBiological invasions stand among the main anthropogenic threats to ecosystems globally while causing multitrillion-dollar impacts. Surprisingly, while trait-based frameworks have been designed to predict invasion success and invader ecological impacts, no such approaches exist to understand and predict economic impacts. We propose the first such framework by bridging the evolutionary biology of traits and the escalation of invasion costs. Previously acquired traits can benefit performance, and their rapid change could exacerbate impacts through adaptive and non-adaptive processes during invasion, such as natural selection, genetic drift, or phenotypic plasticity. Emerging evidence suggests that some organismal traits can determine economic impact magnitudes. We discuss new transdisciplinary avenues that can inform cost forecasting and management responses for current and future biological invasions. © 2025 The Author(s
Schritt für Schritt in den Open Access. Eine Handreichung für wissenschaftliche Fachgesellschaften
No full textDie Handreichung wurde im Rahmen des BMBF-geförderten Projekts open-access.network entwickelt und richtet sich an Vorstände, Geschäftsstellen und Mitglieder wissenschaftlicher Fachgesellschaften. Sie bietet praxisnahe Empfehlungen für die Umsetzung der Open-Access-Transformation. Grundlage sind Auswertungen von Gesprächen und Workshops mit Vertreter*innen verschiedener Fachgesellschaften. Die beschriebenen Handlungsfelder und Strategien zeigen konkrete Ansätze auf und werden durch Beispiele ergänzt, die mögliche Wege zur Einführung und Förderung von Open Access illustrieren
2. Wochenbericht Reise SO312
No full textForschungsschiff SONNE Reise SO312, BRASS Brothers Volcano Seismic Structure, Auckland, 04.05.2025 - 31.05.2025.
2. Wochenbericht (12. - 18.05.2025
Detecting small seamounts in multibeam data using convolutional neural networks
No full textSeamounts play a crucial role in marine ecosystems, ocean circulation, and plate tectonics, yet most remain unmapped due to limitations in detection methods. While satellite altimetry provides large-scale coverage, its resolution is insufficient for detecting smaller seamounts, necessitating high-resolution multibeam bathymetry. This study introduces a deep-learning-based framework for automated small seamount detection in multibeam bathymetry, combining a CNN-based filtering step with U-Net segmentation to enhance accuracy and efficiency.Using multibeam bathymetric data from the SO305-2 expedition, the proposed approach successfully identified 30 seamounts, many of which were undetectable using satellite altimetry.A hyperparameter optimization study determined the optimal U-Net configuration, achieving a Dice Coefficient of 0.8274 and a Mean IoU of 0.7514. While the model performed well within the training dataset, cross-regional generalization remains challenging, with reduced accuracy observed in areas of highly variable seafloor morphology.The results highlight the limitations of satellite altimetry, as only 14 of the 30 detected seamounts were visible in satellite-derived datasets. This underscores the necessity of high-resolution multibeam surveys for capturing fine-scale seafloor features. In contrast to time-intensive manual annotation-which can require several hours to accurately delineate each individual seamount-the automated U-Net-based segmentation approach analyzed 146,060 km² of multibeam data within seconds, offering substantial time savings and scalability for largescale mapping efforts. Beyond geological mapping, automated seamount detection has broad applications in marine ecology, environmental monitoring, and plate tectonics research. Future work should focus on integrating physical principles and geological constraints, such as typical seamount morphology, size distributions, and tectonic setting, to improve classification accuracy
On the potential of Stommel’s perpetual salt fountain for artificial upwelling
No full textArtificial Upwelling (AU) of nutrient-rich deep ocean water to the surface ocean has been proposed to increase ecosystem productivity and enhance CO2 uptake. AU is thus considered a marine Carbon Dioxide Removal (CDR) option among other potential uses. Due to the typical temperature and salinity depth profiles in wide parts of the oceans, a self-sustaining up or downflow within a vertical pipe can be established. This concept was introduced by Stommel et al. (1956) as the perpetual salt fountain. Using a one-dimensional numerical performance prediction method for Stommel Upwelling Pipe (SUP) systems, previously developed and verified by the authors (Kemper et al. 2025), several studies on the potential of the SUP concept for AU are reported in the present work. A global assessment of the AU potential of SUP systems is presented, and the spatial and temporal variability of their performance is discussed. Additionally, an overview of upscaling and optimization design considerations for SUP systems is given based on a parametric study. Our results show that considerable parts of the global oceans are suitable for SUP-based AU of nutrients. The highest potential is found in the subtropical ocean gyres. We further find a significant seasonal pattern in the upwelling velocity. Upscaling of SUP systems to achieve practically significant flow rates for AU is found possible
Potential impacts of marine carbon dioxide removal on ocean oxygen
No full textGlobal warming is a main cause for current ocean deoxygenation. A deployment of marine carbon dioxide removal (CDR) for mitigating global warming could therefore also be viewed as a measure for mitigating ocean deoxygenation if, and only if, the respective CDR measure itself does not lead to a larger oxygen loss than the reduction in atmospheric CO2 would prevent. We here review the current state of knowledge regarding the potential impacts of various marine CDR options onto ocean oxygen, a key ocean state variable and an essential element for all higher forms of marine life. Using results from global model simulations, we show that biotic approaches, such as ocean fertilization, macroalgae cultivation and sinking, and placement of organic matter that is prone to remineralization, can lead to a loss in seawater dissolved oxygen that is 4 to 44 times larger than the oxygen gain that would result from the CDR-induced reduction in global warming only. Biotic approaches also tend to enhance the amplitude of the diel cycle in dissolved oxygen, with possible physiological impacts specifically in shallow-water environments of coastal vegetated ecosystem. In contrast, geochemical approaches, and biotic approaches that avoid remineralization of biomass within the ocean, may be applied in ways that have minimal impacts on dissolved oxygen. We suggest that impacts on marine oxygen should be accounted for in assessing the suitability of marine CDR, and that oxygen should be measured prior to, during and after any research-scale or full-scale implementation activity
CDRmare Insights: Die sechs wichtigsten Forschungsergebnisse zu Verfahren des künstlichen Auftriebes
No full textIm CDRmare-Forschungsverbund zu künstlichem Ozeanauftrieb haben Wissenschaftler*innen in den zurückliegenden drei Jahren untersucht, ob Mikroalgen verstärkt wachsen und sich damit die biologische Kohlenstoffpumpe des Meeres klimawirksam verstärken ließe, wenn man in ausgewählten Regionen des Ozeans nährstoffreiches Tiefenwasser an die Meeresoberfläche pumpt. Ihre sechs wichtigsten Erkenntnisse zur Machbarkeit der Verfahren, zu möglichen Risiken und zu fehlenden Rahmenbedingungen stellen wir hier in Kurzform vor
Variations in Event-Bed Thickness-Frequency Distributions Near Volcanic Islands: Indicators of Varied Geological Processes
No full textA variety of subaerial and submarine events, including mass-wasting and volcanism, can generate sediment gravity flows and fallout deposits that are preserved in deep-water stratigraphic records. This study examines whether event beds with differing depositional and transport histories exhibit distinct thickness-frequency distributions. Analyzing over 4,500 event beds from seven drilling sites near Montserrat, the Izu Arc, the Kyushu-Palau Ridge, and Gran Canaria, the analyses explore variations in event-bed characteristics across different climatic periods, volcanic stages, and geomorphological settings. Statistical methods include characterizing thickness-frequency distributions and assessing subset similarity using t-tests and smoothed distribution patterns. The data-driven results indicate discernible differences where dominant geological processes vary. For example, volcanic growth stages at the Kyushu–Palau Ridge produced thicker, coarser, and more frequent event beds compared with quiescent stages. Similarly, beds from the north slope of Gran Canaria—where submarine canyons enhanced sediment delivery—were nearly twice as thick as those from the south. In contrast, indistinguishable characteristics between the rear and frontal Izu Arc subsets after 3 Ma are attributed to the development of an extensional zone supplying material to both arc sides. Comparable distributions were also observed within intervals with minimal geological differences. The reliability of this analytical approach depends on high-quality sediment recovery, as drilling-related disturbances may obscure primary depositional signals. Beyond stratigraphic characterization, the method shows broader potential for identifying the provenance of volcanic glass shards through geochemical comparisons and for evaluating the statistical compatibility of data sets from neighboring sites, ensuring sufficient sample size for robust integrated analyses.
Key Points
Variations in event-bed thickness-frequency distribution could indicate differing dominant geological processes
Combining t-tests with thickness-frequency distribution characteristics supports interpretations
Broader applications include tracing the provenance of volcanic material and assessing cross-data set compatibility for integrated analyses
Plain Language Summary
This study investigates whether (a) variations in event-bed layers reflect shifts in geological processes across space and time, and (b) whether these variations can be detected using statistical methods. To address these questions, more than 4,500 event beds were extracted from seven drilling sites around volcanic islands and arcs, grouped based on climate periods, volcanic stages, and seafloor morphological features. By characterizing the occurrence of event bed thickness (thickness–frequency distributions) and employing hypothesis testing (T-tests) to compare distribution similarity, the study links distinct distribution patterns to varying dominant geological processes. For example, event beds during active volcanic phases at the Kyushu–Palau Ridge were thicker, coarser, and more frequent than during quieter phases. Likewise, event beds in northern Gran Canaria—where submarine canyons enhance sediment delivery—were nearly twice as thick as those in the south. In contrast, similar depositional patterns were observed across the Izu Arc after 3 Ma, when a shared sediment source developed in between. Overall, this study provides a valuable approach for statistically identifying distinct stratigraphic records shaped by varying geological factors. The method also shows a broader potential for tracing the origin of volcanic material and assessing whether data sets can be reliably combined for larger-scale statistical analysis
Jugend Forscht Jury Landeswettbewerb 2025, Jury Member for Geoscience/Astronomy
No full textEvaluation and grading of Jugend Forscht project
Reduction of carbon, alkalinity and nutrient fluxes in the southern Baltic Sea caused by dragging of otter trawl nets across the seafloor
No full textMobile bottom-contacting fishing (MBCF) represents a substantial anthropogenic disturbance, significantly disrupting seafloor integrity and altering oceanic carbon storage. In this study, we conducted a benthic trawling experiment on organic-rich muddy sediments in the Mecklenburger Bight, southern Baltic Sea, employing an otter trawl. Multiple trawl tracks were made to assess the temporal impact of bottom fishing on the benthic ecosystem over time scales ranging from days to weeks. Focus was on the wide area where the net footrope was dragged between the otter boards, rather than on much smaller area impacted by the trawl doors. This study constitutes the first comprehensive investigation to systematically monitor the effects of MBCF on benthic oxygen, carbon, alkalinity and nutrient fluxes using autonomous in situ lander measurements. Seafloor observations revealed a profound impact of trawling on seafloor morphology. Flux measurements, coupled with sediment data, indicated reductions in benthic fluxes of O2, dissolved inorganic carbon (DIC), total alkalinity (TA), and nutrients (, , and H4SiO4) within trawled areas compared to control sites. Additionally, observed decreases in organic carbon remineralization rates suggest that MBCF alters benthic respiration by disrupting key biogeochemical processes. Fluxes of O2, DIC, and TA had not returned to baseline levels by the conclusion of the 16 d observation period, indicating prolonged disturbance effects, although natural temporal variations may have an influence. Despite substantial alterations to the benthic biogeochemical pathways, modeling suggests that the reduction in benthic DIC and TA fluxes exerts only a minor influence on CO2 release to the atmosphere compared to the potential impact of pyrite oxidation in resuspended sediment