• European Marine Science
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It is a golden age for animal movement studies and so an opportune time to assess priorities for future work. We assembled 40 experts to identify key questions in this field, focussing on marine megafauna, which include a broad range of birds, mammals, reptiles, and fish. Research on these taxa has both underpinned many of the recent technical developments and led to fundamental discoveries in the field. We show that the questions have broad applicability to other taxa, including terrestrial animals, flying insects, and swimming invertebrates, and, as such, this exercise provides a useful roadmap for targeted deployments and data syntheses that should advance the field of movement ecology. Workshop funding was granted to M.T., A.M.M.S., and C.M.D. by the UWA Oceans Institute, the Australian Institute of Marine Science, and the Office of Sponsored Research at King Abdullah University of Science and Technology (KAUST). Hays, Graeme C. et al. Peer reviewed

It is becoming increasingly clear that the genetic diversity and abundance of antimicrobial resistance (AMR) in non-clinical settings has been underestimated and that the environment plays an integral role in enabling the development of AMR. Due to specific demographic and environmental factors the Gulf Cooperation Council (GCC) region may be particularly susceptible to the threat of AMR, with the marine and aquatic environment potentially playing a specific role in its development and propagation. The demographic factors include rapid population growth, significant international population movements, heavy antibiotic use and insufficient antibiotic stewardship. Environmental factors leading to susceptibility include notable inputs of untreated sewage effluent, high ambient water temperatures, elevated concentrations of heavy metals, and poorly regulated use of antimicrobials in veterinary settings. However, to date there is only a limited understanding of the role that this environment plays in enabling the emergence and propagation AMR in this region. This article provides an overview of the risk associated with AMR in the marine and aquatic environment in the GCC region and proposes a framework for understanding how such environments interact with the wider development and propagation of resistance. It identifies priority actions aligned with the World Health Organisation AMR Global Action Plan and associated national action plans to evaluate the role of marine and aquatic systems relative to the wider factors driving AMR emergence and propagation. The proposed framework and actions to evaluate the role of marine and aquatic environments in driving propagation and emergence of AMR are equally applicable at the regional and national level beyond the GCC. Keywords: AMR, Bacteria, GCC, Emergence, Marine pollution

Phytoplankton assemblages were studied to characterize the trophic status of the semienclosed Vlora Bay (Albania) and to evaluate the influence of terrestrial inputs on its pelagic ecosystem. The study was carried out as part of the European Project CISM (INTERREG IIIA Italy–Albania) and conducted during two oceanographic cruises (spring 2007, winter 2008). The size-fractionated chlorophyll a concentrations, primary production rates, and the chemotaxonomic composition (high-performance liquid chromatography) of the phytoplankton assemblages were measured. The spatial variability of primary production rates and chlorophyll a concentrations both showed a pronounced E-W gradient in the surface layer, with the highest values along the eastern coast. In spring, a deep chlorophyll maximum was observed in the central western part of the bay, whereas in winter a homogeneous vertical distribution was observed. The phytoplankton assemblages were quite similar in both seasons and were dominated by the picophytoplankton fraction (<46% and 53% in spring and in winter, respectively). Haptophytes and pelagophytes were the major phytoplankton groups, and accounted, respectively, for 50% and 15% in spring, and 40% and 25% in winter. The results showed that Vlora Bay was characterized by generally oligotrophic conditions and that the influence of the southern Adriatic open waters was negligible. The trophic characteristics of the pelagic ecosystem of the bay were essentially driven by terrestrial inputs.

Abstract. The rewetting of drained peatlands alters peat geochemistry and often leads to sustained elevated methane emission. Although this methane is produced entirely by microbial activity, the distribution and abundance of methane-cycling microbes in rewetted peatlands, especially in fens, is rarely described. In this study, we compare the community composition and abundance of methane-cycling microbes in relation to peat porewater geochemistry in two rewetted fens in northeastern Germany, a coastal brackish fen and a freshwater riparian fen, with known high methane fluxes. We utilized 16S rRNA high-throughput sequencing and quantitative polymerase chain reaction (qPCR) on 16S rRNA, mcrA, and pmoA genes to determine microbial community composition and the abundance of total bacteria, methanogens, and methanotrophs. Electrical conductivity (EC) was more than 3 times higher in the coastal fen than in the riparian fen, averaging 5.3 and 1.5 mS cm−1, respectively. Porewater concentrations of terminal electron acceptors (TEAs) varied within and among the fens. This was also reflected in similarly high intra- and inter-site variations of microbial community composition. Despite these differences in environmental conditions and electron acceptor availability, we found a low abundance of methanotrophs and a high abundance of methanogens, represented in particular by Methanosaetaceae, in both fens. This suggests that rapid (re)establishment of methanogens and slow (re)establishment of methanotrophs contributes to prolonged increased methane emissions following rewetting.

The NMR-based configurational analysis of complex marine natural products is still not a routine task. Different NMR parameters are used for the assignment of the relative configuration: NOE/ROE, homo- and heteronuclear J couplings as well as anisotropic parameters. The combined distance geometry (DG) and distance bounds driven dynamics (DDD) method allows a model-free approach for the determination of the relative configuration that is invariant to the choice of an initial starting structure and does not rely on comparisons with (DFT) calculated structures. Here, we will discuss the configurational analysis of five complex marine natural products or synthetic derivatives thereof: the cis-palau’amine derivatives 1a and 1b, tetrabromostyloguanidine (1c), plakilactone H (2), and manzamine A (3). The certainty of configurational assignments is evaluated in view of the accuracy of the NOE/ROE data available. These case studies will show the prospective breadth of application of the DG/DDD method.

Dinoflagellates are haploid eukaryotic microalgae in which rapid proliferation causes dense blooms, with harmful health and economic effects to humans. The proliferation mode is mainly asexual, as the sexual cycle is believed to be rare and restricted to stressful environmental conditions. However, sexuality is key to explaining the recurrence of many dinoflagellate blooms because in many species the fate of the planktonic zygotes (planozygotes) is the formation of resistant cysts in the seabed (encystment). Nevertheless, recent research has shown that individually isolated planozygotes in the lab can enter other routes besides encystment, a behavior of which the relevance has not been explored at the population level. In this study, using imaging flow cytometry, cell sorting, and Fluorescence In Situ Hybridization (FISH), we followed DNA content and nuclear changes in a population of the toxic dinoflagellate Alexandrium minutum that was induced to encystment. Our results first show that planozygotes behave like a population with an “encystment-independent” division cycle, which is light-controlled and follows the same Light:Dark (L:D) pattern as the cycle governing the haploid mitosis. Resting cyst formation was the fate of just a small fraction of the planozygotes formed and was restricted to a period of strongly limited nutrient conditions. The diploid-haploid turnover between L:D cycles was consistent with two-step meiosis. However, the diel and morphological division pattern of the planozygote division also suggests mitosis, which would imply that this species is not haplontic, as previously considered, but biphasic, because individuals could undergo mitotic divisions in both the sexual (diploid) and the asexual (haploid) phases. We also report incomplete genome duplication processes. Our work calls for a reconsideration of the dogma of rare sex in dinoflagellates. SI

Abstract The dynamics of diatoms and dinoflagellates have been monitored for many decades at the Helgoland Roads Long-Term Ecological Research site and are relatively well understood. In contrast, small-sized eukaryotic microbes and their community changes are still much more elusive, mainly due to their small size and uniform morphology, which makes them difficult to identify microscopically. By using next-generation sequencing, we wanted to shed light on the Helgoland planktonic community dynamics, including nano- and picoplankton, during a spring bloom. We took samples from March to May 2016 and sequenced the V4 region of the 18S rDNA. Our results showed that mixotrophic and heterotrophic taxa were more abundant than autotrophic diatoms. Dinoflagellates dominated the sequence assemblage, and several small-sized eukaryotic microbes like Haptophyta, Choanoflagellata, Marine Stramenopiles and Syndiniales were identified. A diverse background community including taxa from all size classes was present during the whole sampling period. Five phases with several communities were distinguished. The fastest changes in community composition took place in phase 3, while the communities from phases 1 to 5 were more similar to each other despite contrasting environmental conditions. Synergy effects of next-generation sequencing and traditional methods may be exploited in future long-term observations.