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ispartof: COMPUTER PHYSICS COMMUNICATIONS vol:297 status: accepted

This repository contains files and scripts used to generate figures for the paper titled "A detectable change in the air-sea CO2 flux estimate from sailboat measurements". The study quantifies the impact of pCO2 observations measured by the sailboat "Seaexplorer" on the air-sea CO2 flux estimate. Overview: We used pCO2 measurements sourced from SOCAT (www.socat.info), along with other environmental variables. We applied the 2-step neural network method SOM-FFN (Landschützer et al., 2013) to reconstruct air-sea CO2 flux estimates. Four sets of air-sea CO2 flux estimates were reconstructed, each with 40 ensemble members to account for random errors in the neural network. These are the four sets: E1) fluxesA - Based on SOCATv2022 including Seaexplorer data E2) fluxesB - Based on SOCATv2022 excluding Seaexplorer data. E3) fluxesC - Based on SOCATv2022 data, including Seaexplorer data, but introducing a random uncertainty of ± 5 μatm to the Seaexplorer data. E4) fluxesD - Based on SOCATv2022 data, including Seaexplorer data, but introducing a constant measurement offset of 5 μatm to the Seaexplorer data. These air-sea CO2 flux density estimates are 4-dimensional, represented in mol C m-2 yr-1, with the following dimensions: - Ensemble size of flux reconstructions (40) - Time (months from 1982 to 2021, totaling 480 months) - Latitude (1-degree intervals, totaling 180 latitudes) - Longitude (1-degree intervals, totaling 360 longitudes)

AbstractProgress in mechanobiology allowed us to better understand the important role of mechanical forces in the regulation of biological processes. Space research in the field of life sciences clearly showed that gravity plays a crucial role in biological processes. The space environment offers the unique opportunity to carry out experiments without gravity, helping us not only to understand the effects of gravitational alterations on biological systems but also the mechanisms underlying mechanoperception and cell/tissue response to mechanical and gravitational stresses. Despite the progress made so far, for future space exploration programs it is necessary to increase our knowledge on the mechanotransduction processes as well as on the molecular mechanisms underlying microgravity-induced cell and tissue alterations. This white paper reports the suggestions and recommendations of the SciSpacE Science Community for the elaboration of the section of the European Space Agency roadmap “Biology in Space and Analogue Environments” focusing on “How are cells and tissues influenced by gravity and what are the gravity perception mechanisms?” The knowledge gaps that prevent the Science Community from fully answering this question and the activities proposed to fill them are discussed.

Gobies (Gobiidae) are well represented in the Marchica Lagoon on the Moroccan Mediterranean coast, both in terms of species richness and in terms of abundance, with the black goby, Gobius niger Linnaeus, 1758, being the dominant species. The present study aims to examine (1) the spatial and temporal distribution of G. niger and its environmental drivers in the lagoon and (2) the potential lagoon-related footprint using morphometric, genetic, and parasitological proxies. Systematic monthly sampling covering the whole lagoon basin performed between October 2015 and September 2016 revealed a year-long presence of G. niger throughout the lagoon with significantly low densities in winter. The highest abundances were recorded in the shallow bottoms of the lagoon’s inner margins on a variety of substrates (mud, muddy-sand, sandy-mud, and fine sand) mostly covered by macroalgae and/or seagrass meadows. Depth was revealed to be the most important predictor of the distribution of the black goby in the lagoon. It should, however, be regarded as a variable that acts synergistically with other factors, such as temperature, vegetation cover, and the sediment’s mean grain size. Comparison of black goby populations from the lagoon with their conspecifics from the adjacent Mediterranean coast of Morocco revealed that specimens caught at sea are larger than those of the lagoon population. Of the 180 gobies investigated, not a single one hosted the parasites we targeted in the parasitological approach, monogenean flatworms. The absence of population structuring, low genetic diversity, and the presence of common haplotypes indicate no apparent restriction in the gene flow between the two populations. Therefore, the observed morphometric differences seem to be due to external environmental conditions rather than genetic differences. This research was supported by the Special Research Fund of Hasselt University (BOF23BL07 to A.L.; BOF-21PD01 to N.K.; BOF20TT06 to M.P.M.V.; BOF21IN-CENT09) and by research grant 1513419N of the Re-search Foundation – Flanders (FWO-Vlaanderen). The sampling survey was undertaken in the framework of an international cooperation between Le Conservatoire du Littoral, Agence de l’Eau Rhône-Méditerranée-Corse, the Ecocean Society, University Mohammed V in Rabat, Institut National de Recherche Halieutique, Observatoire de la Marchica, and Fondation Mohammed VI pour la Protection de l’Environnement. M.S. thanks the Agence de l’Eau Rhône Méditerranée Corse and the Ecocean Society for their financial support. The authors are very grateful to fishers for providing G. niger samples from both the Marchica Lagoon and the adjacent Mediterrane-an coast of Morocco. Dr. Lukas Rüber (Natural History Museum of Bern, Switzerland) is thanked for curatorial services

To better understand the fate and assess the ingestible fraction of microplastics (by aquatic organisms), it is essential to quantify and characterize of their released from larger items under environmental realistic conditions. However, the current information on the fragmentation and size-based characteristics of released microplastics, for example from bio-based thermoplastics, is largely unknown. The goal of our work was to assess the fragmentation and release of microplastics, under ultraviolet (UV) radiation and in seawater, from polylactic acid (PLA) items, a bio-based polymer, and from polypropylene (PP) items, a petroleum-based polymer. To do so, we exposed pristine items of PLA and PP, immersed in filtered natural seawater, to accelerated UV radiation for 57 and 76 days, simulating 18 and 24 months of mean natural solar irradiance in Europe. Our results indicated that 76-day UV radiation induced the fragmentation of parent plastic items and the microplastics (50 - 5000 µm) formation from both PP and PLA items. The PP samples (48 ± 26 microplastics / cm2) released up to nine times more microplastics than PLA samples (5 ± 2 microplastics / cm2) after a 76-day UV exposure, implying that the PLA tested items had a lower fragmentation rate than PP. The particles’ length of released microplastics was parameterized using a power law exponent (α), to assess their size distribution. The obtained α values were 3.04 ± 0.11 and 2.54 ± 0.06 (-) for 76-day UV weathered PP and PLA, respectively, meaning that PLA microplastics had a larger sized microplastics fraction than PP particles. With respect to their two-dimensional shape, PLA microplastics also had lower width-to-length ratio (0.51 ± 0.17) and greater fiber-shaped fractions (16%) than PP microplastics (0.57 ± 0.17% and 11%, respectively). Overall, the bio-based PLA items under study were more resistant to fragmentation and release of microplastics than the petroleum-based PP tested items, and the parameterized characteristics of released microplastics were polymer-dependent. Our work indicates that even though bio-based plastics may have a slower release of fragmented particles under UV radiation compared to conventional polymer types, they still have the potential to act as a source of microplastics in the marine environment, with particles being available to biota within ingestible size fractions, if not removed before major fragmentation processes.

We present chromosome-level genome assemblies from representative species of three independently evolved seagrass lineages: Posidonia oceanica, Cymodocea nodosa, Thalassia testudinum and Zostera marina. We also include a draft genome of Potamogeton acutifolius, belonging to a freshwater sister lineage to Zosteraceae. All seagrass species share an ancient whole-genome triplication, while additional whole-genome duplications were uncovered for C. nodosa, Z. marina and P. acutifolius. Comparative analysis of selected gene families suggests that the transition from submerged-freshwater to submerged-marine environments mainly involved fine-tuning of multiple processes (such as osmoregulation, salinity, light capture, carbon acquisition and temperature) that all had to happen in parallel, probably explaining why adaptation to a marine lifestyle has been exceedingly rare. Major gene losses related to stomata, volatiles, defence and lignification are probably a consequence of the return to the sea rather than the cause of it. These new genomes will accelerate functional studies and solutions, as continuing losses of the ‘savannahs of the sea’ are of major concern in times of climate change and loss of biodiversity.

This folder contains the electronic supplementary materials for: "Chapter 5. Osmoregulation underpins functional stability of Ulva-associated bacterial communities in the Baltic Sea" which is part of the PhD thesis "Ulva-microbial interactions linked to the environment: variation and acclimation" by Luna van der Loos (submitted in 2024) Contents: Table S1: metadata of 91 samples Table S2: metadata of bacterial genomes used in the comparison between seawater and Ulva-derived bacteria Table S3: overview of the 639 Ulva-associated MAGs Table S4: overview of the KEGG modules identified in each MAG Supplementary Figures: additional figures