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Effective monitoring of non-indigenous seaweeds and combatting their effects relies on a solid confirmation of the non-indigenous status of the respective species. We critically analysed the status of presumed non-indigenous seaweed species reported from the Mediterranean Sea, the Northeast Atlantic Ocean and Macaronesia, resulting in a list of 140 species whose non-indigenous nature is undisputed. For an additional 87 species it is unclear if they are native or non-indigenous (cryptogenic species) or their identity requires confirmation (data deficient species). We discuss the factors underlying both taxonomic and biogeographic uncertainties and outline recommendations to reduce uncertainty about the non-indigenous status of seaweeds. Our dataset consisted of over 19,000 distribution records, half of which can be attributed to only five species (Sargassum muticum, Bonnemaisonia hamifera, Asparagopsis armata, Caulerpa cylindracea and Colpomenia peregrina), while 56 species (40%) are recorded no more than once or twice. In addition, our analyses revealed considerable variation in the diversity of non-indigenous species between the geographic regions. The Eastern Mediterranean Sea is home to the largest fraction of non-indigenous seaweed species, the majority of which have a Red Sea or Indo-Pacific origin and have entered the Mediterranean Sea mostly via the Suez Canal. Non-indigenous seaweeds with native ranges situated in the Northwest Pacific make up a large fraction of the total in the Western Mediterranean Sea, Lusitania and Northern Europe, followed by non-indigenous species with a presumed Australasian origin. Uncertainty remains, however, regarding the native range of a substantial fraction of non-indigenous seaweeds in the study area. In so far as analyses of first detections can serve as a proxy for the introduction rate of non-indigenous seaweeds, these do not reveal a decrease in the introduction rate, indicating that the current measures and policies are insufficient to battle the introduction and spread of non-indigenous species in the study area. European Marine Biological Resource Centre Belgium [GOH3817N]; European Marine Biological Resource Centre Belgium [I001621N]; Fonds Wetenschappelijk Onderzoek [3F020119]; POR PUGLIA FESR-FSE 2014/2020 [Asse VI, Action 6.5]; RESTORESEAS [EU-BiodivERsA BiodivRestore-253]; Institut des Sciences de l’Évolution – Montpellier [ISEM 2023-173]; Italian National Recovery and Resilience Plan [Mission 4, Component 2, ‘From research to business’: 1. NBFC, Investment 1.4, Project CN00000033]; IDEALG [ANR-10-BTBR-04; Institut des Sciences de l’Évolution – Montpellier Institut des Sciences de l’Évolution – Montpellier [ISEM 2023-173]. info:eu-repo/semantics/publishedVersion

AbstractBackgroundChronic obstructive pulmonary disease (COPD) is a complex disorder with a high degree of interindividual variability. Gastrointestinal dysfunction is common in COPD patients and has been proposed to influence the clinical progression of the disease. Using the presence of bile acid(s) (BA) in bronchoalveolar lavage fluid (BAL) as a marker of gastric aspiration, we evaluated the relationships between BAs, clinical outcomes, and bacterial lung colonisation.MethodsWe used BAL specimens from a cohort of COPD patients and healthy controls. Bile acids were profiled and quantified in BAL supernatants using mass spectrometry. Microbial DNA was extracted from BAL cell pellets and quantified using qPCR. We profiled the BAL microbiota using an amplicon sequencing approach targeting the V3-V4 region of the 16S rRNA gene.ResultsDetection of BAs in BAL was more likely at earliest clinical stages of COPD and was independent of the degree of airway obstruction. BAL specimens with BAs demonstrated higher bacterial biomass and lower diversity. Likewise, the odds of recovering bacterial cultures from BAL were higher if BAs were also detected. Detection of BAs in BAL was not associated with either inflammatory markers or clinical outcomes. We also observed different bacterial community types in BAL, which were associated with different clinical groups, levels of inflammatory markers, and the degree of airway obstruction.ConclusionDetection of BAs in BAL was associated with different parameters of airway ecology. Further studies are needed to evaluate whether BAs in BAL can be used to stratify patients and for predicting disease progression trajectories.

Manta and devil rays (mobulids) are filter feeding elasmobranchs with extreme K-selective life histories found circumglobally from temperate to tropical waters. Their vulnerability to fisheries exploitation, bycatch, boat collisions, entanglement and unregulated tourism is exacerbated by their aggregative behavior. Studies have identified aggregation sites around the world for all nine mobulid species, with these groupings varying from a few individuals to thousands. However, the terminology used to define these aggregations and the drivers underpinning them remain unclear, hindering the development of effective management and conservation strategies. Here, we analyze aggregation behavior for mobulid species, providing consistent definitions for grouping events and summarizing the existing research on drivers and environmental factors triggering these events. We find that aggregation behaviors facilitate socializing and key life history functions in mobulids, including feeding, courtship and mating, predation avoidance, cleaning, and thermoregulation. Conservation threats and management mitigation opportunities associated with aggregations sites include fisheries, tourism, spatial protection, and climate change. Finally, we highlight knowledge gaps for future research prioritization and developments in the field for the identification of aggregation sites, the study of aggregation size and demographics and the functions and timing of aggregations.

Toxic species of the dinoflagellate genus Dinophysis can produce diarrheic toxins including okadaic acid (OA) and dinophysistoxins (DTXs), and the non-diarrheic pectenotoxins (PTXs). Okadaic acid and DTXs cause diarrheic shellfish poisoning (DSP) in human consumers, and also cause cytotoxic, immunotoxic and genotoxic effects in a variety of mollusks and fishes at different life stages in vitro. The possible effects of co-produced PTXs or live cells of Dinophysis to aquatic organisms, however, are less understood. Effects on an early life stage of sheepshead minnow (Cyprinodon variegatus), a common finfish in eastern USA estuaries, were evaluated using a 96-h toxicity bioassay. Three-week old larvae were exposed to PTX2 concentrations from 50 to 4000 nM, live Dinophysis acuminata culture (strain DAVA01), live cells resuspended in clean medium or culture filtrate. This D. acuminata strain produced mainly intracellular PTX2 (≈ 21 pg cell − 1), with much lower levels of OA and dinophysistoxin-1. No mortality or gill damages were observed in larvae exposed to D. acuminata (from 5 to 5500 cells mL − 1), resuspended cells and culture filtrate. However, exposure to purified PTX2 at intermediate to high concentrations (from 250 to 4000 nM) resulted in 8 to 100% mortality after 96 h (24-h LC 50 of 1231 nM). Histopathology and transmission electron microscopy of fish exposed to intermediate to high PTX2 concentrations revealed important gill damage, including intercellular edema, necrosis and sloughing of gill respiratory epithelia, and damage to the osmoregulatory epithelium, including hypertrophy, proliferation, redistribution and necrosis of chloride cells. Tissue damage in gills is likely caused by the interaction of PTX2 with the actin cytoskeleton of the affected gill epithelia. Overall, the severe gill pathology observed following the PTX2 exposure suggested death was due to loss of respiratory and osmoregulatory functions in C. variegatus larvae. International audience

Intercropping, also known as mixed cropping, consists on simultaneously growing more than one species on a field. It has a great potential for enhancing water- and nutrientuse efficiency and improving plant productivity, yield stability and resilience to biotic and abiotic stress, including those triggered by climate change. Despite their manifold benefits, the practice of intercropping has not risen above its niche status in many regions of the world. The selection of varieties specifically adapted to intercropping remains a major practical challenge to its widespread deployment. This Editorial of a Research Topic hosted at Frontiers in Plant Sciences entitled “Breeding for intercropping” gathers a series of articles covering new insights in the areas of quantitative genetics, ecology, ecophysiology and agronomy integrating theoretical, experimental as well as participatory approaches.

Reliably recording very low ambient concentrations of gaseous elemental mercury (GEM) in remote regions is often required, for example in the context of evaluating how effective the Minamata Convention is in reducing global Hg emissions. However, sampling over extended periods of time at sites that are difficult to access can be very challenging. In order to establish what role inexpensive and easy-to-use passive air samplers may play in this regard, we deployed a sampler using a Radiello diffusive barrier and activated carbon sorbent for periods of up to three years and with sampling periods ranging from one to three months in some of the most extreme, remote and challenging global environments: at Concordia station on the Antarctic plateau, on Amsterdam Island in the remote Southern Indian Ocean and at several sites on the tropical island of La Reunion. The ability to reliably record the GEM concentrations at these sites was strongly influenced by the size of the sequestered amount of mercury relative to the extent and variability of the contamination of field blank samples. In some cases, acceptably low and consistent field blank contamination could only be achieved by storing samplers in sealed glass jars during transport and storage. The size of the sequestered amount is easily increased by extending deployment times, and the experience of the current study suggests that deployment periods in excess of two months are advisable. Sampling in Antarctica was compromised by the extreme low temperatures, which caused unknown sampling rates, hoar frost accumulation, material failure and potential failure of storage seals. While good agreement with GEM concentrations measured with an active sampler was noted on Amsterdam Island, the passive sampler derived levels at the Maido Observatory in La Reunion were notably higher than concentrations measured simultaneously with a Tekran vapour analyzer, which was possibly related to sampling rates being temporarily elevated at the very beginning of deployment at low GEM concentrations. Environmental significanceWhereas extremely remote locations, such as Antarctica or isolated islands, are important for studying the troposphere, limitations regarding site access, electrical power, skilled personnel, and specialized supplies can make measurements challenging. Passive sampling approaches without the need for power, maintenance and frequent site visits are attractive, but their performance under the frequently harsh conditions encountered at such sites needs to be established. We tested the feasibility of recording long-term average concentrations of gaseous elemental mercury with a passive sampler at some of the world's most remote and extreme atmospheric research stations. The failures and successes of these tests informed the development of guidelines and procedures that increase the likelihood of obtaining reliable long-term records of atmospheric mercury with passive samplers. International audience

AbstractTropical reefs and the fish relying on them are under increasing pressure. Shallow-reef fish provide important ecological information in addition to sustaining fisheries, tourism and more. Although empirical metrics of fish biomass are widely used in fisheries management, metrics of biomass production—how much new biomass is produced over time—are rarely estimated even though such production informs potential fisheries yields. Here we estimate fish standing biomass (B), biomass production (P, the rate of biomass accumulation) and biomass turnover (P/B ratio, the rate of biomass replacement) for 1,979 tropical reef sites spanning 39 tropical countries. On the basis of fish standing biomass and biomass turnover, we propose a conceptual framework that splits reefs into three classes to visualize ecological and socio-economic risk and help guide spatial management interventions (for example, marine protected areas) to optimize returns on conservation efforts. At large scales, high turnover was associated with high human pressure and low primary productivity, whereas high biomass was associated with low human pressure and high primary productivity. Going beyond standing fish biomass to consider dynamic ecological processes can better guide regional coral reef conservation and sustainable fisheries management.