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The resilience of saltmarshes mainly depends on their ability to gain elevation by sediment accretion to keep pace with sea level rise. While vegetation is known to facilitate sediment accretion at the plant scale by trapping mineral sediments and producing organic matter, the long-term impact at the landscape scale is still poorly understood. Here we use the biogeomorphic model Demeter to reveal contrasting vegetation impacts on spatial patterns of sediment accretion under different sea level rise regimes. Under contemporary sea level rise rates (2-10 mm/yr), vegetation inhibits sediment transport from tidal channels to platform interiors and creates levee-depression patterns. Hence, intertidal platforms accrete slower with vegetation than without, but this trend attenuates with increasing sea level rise rate, as water depth increases, and vegetation drag decreases. Under extreme sea level rise rate (20 mm/yr), platform interiors don’t keep up and turn into open water, while vegetation allows to preserve intertidal levees. Our results help to better understand some basic biophysical mechanisms that will control the fate of coastal wetlands under global climate change.

Tidal marshes are valuable coastal ecosystems that are threatened by global climate warming and the resulting sea level rise. Whether they drown or continue to exist, depends on the trapping of sediments that builds up the land surface. Tidal channel networks, which typically occur within tidal marshes, are the major supply routes for sediments towards the marshes and hence are expected to affect the capacity of marshes to keep up with sea level rise by sediment trapping. The development and evolution of tidal channel networks and the sediment trapping are locally determined by so-called bio-geomorphic interactions between plants, water flow and sediment transport. However, the effect of different environmental variables on channel network formation remains poorly understood. In this research, we investigated the impact of spatio-temporal plant colonization patterns by means of flume experiments. Four scaled landscape scale experiments were conducted in the Metronome tidal facility, a unique flume that tilts periodically to generate tidal currents. Two control experiments without vegetation, a third experiment with a channel-fringing vegetation colonization pattern, and a fourth with patchy vegetation colonization pattern. Seeds were distributed by water in the channel-fringing experiment, while a manual sowing method was used to obtain laterally expanding circular patches in the patchy experiment. Our results show that vegetation and their respective colonization pattern affect channel network formation both on a landscape scale and local scale. More extensive and effective channel networks are found in vegetation experiments. These results indicate that channel-fringing or patchy recruitment strategies might produce landscapes that are more resilient to sea level rise.

Biogeomorphic interactions between tidal channels and marsh plants play a crucial role in enhancing coastal resilience to climate change. Previous studies linking the channel formation with vegetation dynamics predominantly focused on the early initiation, characterized by local-scale plant-flow feedbacks. However, the influence of rapid changes in landscape-scale vegetation pattern on the channel initiation remains poorly understood, especially in micro-tidal system. In this study, we investigated this relationship through biogeomorphic modeling combined with the analysis of satellite images in a rapidly expanding marsh in China under Spartina alterniflora invasion. The satellite images demonstrated the increase in drainage density and the decrease in unchanneled path length following plant encroachment. Our modeling results showed that local flow acceleration between vegetation patches was insufficient to initiate channels rapidly before the merging of isolated patches under micro-tidal conditions. With plant expansion, the continuous marsh caused landscape flow diversion from homogenous platform flow to concentrated channel flow, which promoted evident tributary channel initiation in the landward marsh zone. The vegetation removal scenarios further highlighted that the flow divergence from adjacent platforms due to the spatial heterogeneity in plant configuration amplified the magnitude of local hydrodynamics and further channel incision. Our findings emphasize that the initiation of tidal channels not only depends on local plant-flow interaction but is largely driven by landscape vegetation configuration under micro-tidal conditions.

The resilience of saltmarshes mainly depends on their ability to gain elevation by sediment accretion to keep pace with sea level rise, and tidal channels play a crucial role in the supply of sediments towards their interiors. While feedbacks between vegetation and geomorphology are increasingly recognized as key drivers shaping a variety of tidal channel network structures, the resulting impact on long-term sediment accretion over the vegetated platforms remains poorly studied. At the plant-scale, vegetation facilitates sediment accretion by trapping mineral sediments and producing organic matter. At the landscape-scale, vegetation promotes the formation of dense, branching, and meandering tidal channel networks, which reduce the distance between saltmarsh interiors and their source of suspended sediments. In this presentation, we use a biogeomorphic model validated against data to reveal two mechanisms by which vegetation also hinders sediment transport towards saltmarsh interiors. First, vegetation concentrates tidal flow and sediment transport inside channels, which reduces sediment availability for deposition on saltmarsh platforms. Secondly, vegetation enhances sediment deposition close to channels, which deprives saltmarsh interiors of suspended sediments, creating levee-depression patterns and leading to pond formation. In the present context of accelerating sea level rise and human-induced decrease of sediment supply, our findings suggest that saltmarshes are more vulnerable than previously thought.

The North Sea is an epeiric sea on the European continental shelf, which connects to the Atlantic Ocean through the English Channel in the South and the Norwegian Sea in the North. It hosts key north European shipping lanes, and it is a major fishery and a rich source of energy resources, including wind and wave power. Here we present a multi-year effort at developing a modeling infrastructure to support research in marine ecology and biogeochemistry in such highly, anthropogenically impacted system, and allow stakeholders taking informed decisions to sustainably manage its valuable resources. Our approach is fully open-source and mainly based on the numerical model COHERENS to simulate hydrodynamical and biogeochemical processes in three spatial dimensions and time. Our model is specifically validated against relevant in situ data in view of its main applications, for which it provides a large-scale virtual laboratory. For example, our model is used to investigate the impact of floating solar panel farms on primary production, but also to assess the efficiency of enhanced silicate weathering to serve as negative emission technology.

The North Sea is an epeiric sea on the European continental shelf, which connects to the Atlantic Ocean through the English Channel in the South and the Norwegian Sea in the North. It hosts key north European shipping lanes, and it is a major fishery and a rich source of energy resources, including wind, wave and solar power. Here we present a nested hydrodynamics model that is calibrated against in situ data for the year 2009, and validated for the years 2010, 2011 and 2015, which present a large range of contrasting North Atlantic Oscillation (NAO) indices. Our results are openly available and provide 10+ years of hydrodynamics data (sea surface elevation, sea water velocity, potential temperature and salinity) with a resolution of 30 arcseconds in the Southern Bight of the North Sea, and 2 arcminutes elsewhere. With our model and resulting dataset, we aim at supporting marine research and policy in a highly, anthropogenically impacted system, allowing stakeholders to take informed decisions to sustainably manage its valuable resources.

The resilience of saltmarshes mainly depends on their ability to gain elevation by sediment accretion to keep pace with sea level rise. While vegetation is known to facilitate sediment accretion at the plant scale by trapping mineral sediments and producing organic matter, the long- term impact at the landscape scale is still poorly understood. Here we use the biogeomorphic model Demeter to reveal contrasting vegetation impacts on spatial patterns of sediment accretion under different sea level rise regimes. Under contemporary sea level rise rates (2-10 mm/yr), vegetation inhibits sediment transport from tidal channels to platform interiors and creates levee- depression patterns. Hence, intertidal platforms accrete slower with vegetation than without, but this trend attenuates with increasing sea level rise rate, as water depth increases, and vegetation drag decreases. Under extreme sea level rise rate (20 mm/yr), platform interiors don’t keep up and turn into open water, while vegetation allows to preserve intertidal levees. Our results help to better understand some basic biophysical mechanisms that will control the fate of coastal wetlands under global climate change.

The DiSSCo (Distributed System of Scientific Collections) Flanders consortium, with one of the set goals being ``maturing'' (i.e., optimizing the management of) and unlocking (i.e., publishing) their DNA collections, identified 1) the need for actively sharing best practices on the management of DNA collections; and 2) a need for guidance on how to bring theory into practice.During the DiSSCo Flanders project, a DNA collection working group was created. The working group is open to all biodiversity-related DNA collections associates in Belgium, including those in diverse roles such as researchers, lab technicians, collection managers and data managers. Around 50 people from 13 organizations are currently participating. Members can be passively (reading only) or actively (joining events) engaged. The strength, as well as one of the challenges, of the DiSSCo Flanders community is that the natural science collections are created and managed in different organizational contexts: universities, museum institutes and both governmental and non-governmental research organizations. This translates to a variety of collection management decisions and structures such as: decentralized or centralized; cold or room temperature storage; managed by an appointed curator or by a lab technician.The working group organizes meetings and workshops, tours of each other's collections, and shares a mailing list and an online document space. As its principal output, the group has co-created: “The key to bringing DNA collections to the next level” (Veltjen et al. 2024) with two main results: the ``Challenges'' and the “Key”.The ``Challenges'' is a list of 23 challenges applicable to DNA collection management. For example, challenge 8: ``Select or customise collection management systems to meet the needs of DNA collections''. They are intended to spark debate and give focus to the second output: the ``Key.'' The ``Key'' lists seven yes/no questions:Do you have an up-to-date overview of all direct, internal stakeholders of the institute’s DNA collection and are you involving them in the (current) intent to “bring the DNA collection to the next level”?Is preserving a DNA collection within the scope of the institute? And is the DNA collection officially recognized within the institute?Do you have, on paper, a clear description of the scope of the DNA collection?Have you outlined the current overarching workflow of the DNA collection?Have you been able to establish your starting level on the ``DNA collection maturation chart'' and is the assessment properly logged?Level up, one level at a time, and log the process. Have you reached all of the goals in level 3 on the ``DNA collection maturation chart''?Do you have a re-evaluation strategy for your DNA collection?The ``DNA collection maturation chart'' has 11 categories (rows), three levels (columns) and 33 goals (see Table 1 in Veltjen et al. 2024). The Key provides 18 guidance chapters, which give in depth information, literature and user experiences (Suppl. material 2 in Veltjen et al. 2024).The Key is a specialized tool for DNA collections. It facilitates a standardized and holistic approach, allowing both a helicopter view of the maturation process and close-up view of specific goals. The working group aims to test the Key, whereby the process of ``leveling up'' is embedded in a community setting: sharing ambitions, setbacks, changes of plans and success stories. The output is ready in its first version. It is published as a reviewable publication, allowing post-publication peer review (Veltjen et al. 2024). The works are expected to evolve through time, depending on user feedback and user experiences.The working group and co-created output are positive examples of how a local community—sometimes managing smaller, or less conspicuous types of natural science collections—can work together and use their unique perspectives, experiences and needs to contribute to the international natural science collection and biobanking communities.

The current Freshwater Animal Diversity Assessment (FADA) comprises an extensive set of global taxa lists for freshwater animal groups. At present, more than 125 thousand described freshwater animal species in more than 11 thousand genera have been documented. However, taxonomy is a living scientific discipline, where new taxa are continuously being described, and existing taxa are being placed in new taxonomic positions. Therefore, after a period of relative inactivity, the BELSPO (Belgian Science Policy) project “infraFADA” (2023-2026) re-establishes the global FADA consortium of taxonomic experts, so that all taxa lists will be brought up to date, both technically and in terms of content. infraFADA will develop a living, updated, and global FADA database, fully in open access and according to the FAIR principles. The infraFADA database is intended for use and consultation by the scientific freshwater community, as well as for interested stakeholders, for example, freshwater ecosystem managers, biodiversity conservationists, and others. Most importantly, FADA will also serve as a taxonomic backbone for other global biodiversity data infrastructures, such as the Catalogue of Life (CoL), the Global Biodiversity Information Facility (GBIF), the Freshwater Information Platform (FIP), and others. As such, FADA will provide a digital and living heritage of freshwater data, building bridges between science and society and helping to sustainably maintain freshwater resources.