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Extracted Spectral Signatures from the Water Column as a Tool for the Prediction of the Structure of a Marine Microbial Community
Get PDFIn this communication, we present an innovative approach leveraging advanced Machine Learning (ML) and Artificial Intelligence (AI) techniques, specifically the Non-Negative Matrix Factorization (NMF) method, to analyze downward and upward light spectra collected by Hyperspectral Ocean Color Radiometer (HyperOCR, HOCR) sensors in the water column. Our work focuses on the development of a robust and efficient tool for unraveling the structure and activities of natural microbial assemblages in the ocean. By applying the NMF method to HyperOCR data, we successfully extracted five spectral signatures, representing unique patterns in the data. These signatures were instrumental in predicting the abundances of various microbial components, including bacteria, heterotrophic nanoflagellates, and picoeukaryotes, showcasing the potential of ML and AI in advancing oceanographic studies. To validate these methods, the study area included a shallow coastal area under the influence of freshwater inflow and an open offshore area with a depth of 100 m. The study sites in coastal and offshore waters (Kaštela Bay and Stončica Vis, respectively) had significantly different hydrographic and microbiological characteristics. Kaštela Bay had lower temperatures and salinity than the site on Vis. We have demonstrated prediction of the structure of the microbial community through application of different AI and ML methods with specific HOCR sensors.publishedVersio
Environmental and behavioural drivers of Antarctic krill distribution at the South Orkney Islands: A regional perspective
Get PDFAntarctic krill (Euphausia superba) is a key species in the marine ecosystem of the Southern Ocean, but is also the target of a commercial fishery, with an important fishing ground in the South Orkney Islands region. The potential for competition for krill between predators and the fishery requires risk management strategies for the fishery, underpinned by an understanding of the key physical and behavioural drivers of krill movement and retention in target areas. Here, we present the results of a regional modelling study, combining a high-resolution ocean-sea ice model and an individual-based model parameterised for krill, to elucidate the roles of oceanographic variability and krill behaviour on patterns of transport and retention on and around the South Orkney Plateau. Simulations suggest that oceanic transport from sources around the Antarctic Peninsula is restricted by the northward flowing Antarctic Slope Current. Around the South Orkney Plateau, anticyclonic flows associated with the Weddell Front and the shelf edge transport krill rapidly towards the main fishing grounds to the northwest of the plateau. Transport onto the shelf and subsequent retention are influenced by the strength and direction of regional winds; weaker on-shelf transport and shorter retention times are associated with stronger westerly and northerly winds. The incorporation of sea-ice associated behaviour, whereby krill are moved with sea ice when sea ice is present, significantly modifies the patterns from purely oceanic transport; it reduces the influence of strong regional oceanic flows and increases transport of krill to the South Orkneys region from the Antarctic Peninsula. The inclusion of diel vertical migration also modifies predicted patterns from oceanic transport, but to a lesser extent, and moderates the impact of including sea-ice associated behaviour. We highlight the importance of understanding the behaviour of krill, including age-dependent behavioural changes in response to sea ice conditions, for modelling and management of Antarctic krill populations.publishedVersio
Levels of mercury, arsenic, cadmium and lead in Northeast Atlantic mackerel (Scomber scombrus) from northern European waters
Get PDFFillets from a total of 1245 Northeast Atlantic mackerel (Scomber scombrus) sampled in different fishing areas of the Northeast Atlantic during 2007–2016 were analysed for mercury, cadmium, arsenic and lead using ICPMS. Mercury levels varied from <0.01 to 0.36 mg/kg wet weight (ww) with a total mean of 0.046 mg/kg ww and were significantly higher in Skagerrak than in the North Sea, the Norwegian Sea and west of Scotland. Cadmium concentrations varied from <0.002 to 0.16 mg/kg ww with a mean value of 0.015 mg/kg ww. Only 0.24 % and 0.16 % of the sampled fish exceeded the EU's maximum levels for cadmium and mercury, respectively. Arsenic levels varied between 0.43 and 6.9 mg/kg ww with a mean value of 2.2 mg/kg ww and showed seasonal variation following variations in fat content. Lead concentrations were low and below the analytical limit of quantification (LOQ) in 97 % of the samples.publishedVersio
Beregning og vurdering av i hvilken grad høringsutkast til nye kostråd vil dekke behov og anbefalinger for næringsstoffer
Get PDFVitenskapskomiteen for mat og miljø (VKM) har vurdert om Helsedirektoratets høringsutkast til nye kostråd fra 22. mars dekker næringsstoffanbefalingene for voksne, inkludert gravide og ammende.' Oppdraget er gitt av Helsedirektoratet, som en del av arbeidet med å revidere kostrådene, og VKMs beregninger og vurderinger er basert på høringsutkastet. VKMs rapport med resultatene fra oppdraget publiseres samtidig som kostrådene. VKMs rapport og konklusjonerne som presenteres gjelder høringsutkast til kostråd, slik de forelå 22. mars 2024. Basert på VKMs arbeid, har Helsedirektoratet valgt å justere enkelte av kostrådene, slik at kritiske næringsstoffer vil dekkes bedre i de endelige kostrådene som ble publiseres 15. august, parallelt med publisering av VKMs rapport. Hovedkonklusjon fra VKMs rapport: VKM konkluderer at et kosthold i tråd med høringsutkastet til nye kostråd sannsynligvis kan være tilstrekkelig for å dekke næringsstoffanbefalingene for de fleste vitaminer og mineraler for de fleste voksne, med noen unntak. Vurderingen omfatter to scenarioer – lavt og høyt – basert på utkast til kostrådene. Disse to scenarioene representerer henholdsvis de laveste og høyeste mengdene av matvaregruppene som omfattes av utkastet til kostrådene; lavt kostrådsscenario og høyt kostrådsscenario. VKM har kun beregnet næringsinnholdet for maten fra mengdene i utkast til kostråd, ikke for det totale kostholdet. –Vi har vurdert om næringsinnholdet dekkes hvis man følger de foreslåtte kostrådene, slik de forelå i mars. Vi konkluderer med at å følge disse sannsynligvis kan være tilstrekkelig for å dekke næringsstoffanbefalingene for de fleste vitaminer og mineraler for de fleste voksne, hvis man spiser et kosthold basert på de høyeste mengdene av matvaregruppene i kostrådsutkastet, sier faglig leder Anine Medin, som har ledet VKMs arbeid. VKMs resultater viser at innholdet av de fleste beregnede vitaminer og mineraler synes å være tilstrekkelig for kvinner og menn i alle aldere ved et kosthold i tråd med høyt kostrådsscenario. Innholdet av vitamin D, kalsium (kun unge voksne), jern (kun kvinner i fertil alder), sink (kun menn) og selen vil imidlertid sannsynligvis kunne være for lavt for en mindre andel kvinner og menn ved et kosthold som tilsvarer høyt scenario. Beregningene viser at i et kosthold i tråd med lavt kostrådsscenario, ligger innholdet av flere næringsstoffer lavere enn i høyt scenario. Innholdet av riboflavin, kalsium, jern (kun kvinner i fertil alder), sink, jod og selen vil sannsynligvis kunne være for lavt for en betydelig andel kvinner og menn ved et kosthold som tilsvarer lavt scenario. Videre vil innholdet av vitamin D, vitamin B6, folat, kalium, og jern (kun menn) kunne være for lavt for en mindre andel kvinner og menn. Gravide og ammende står i en særstilling, fordi de har høyere behov for næringsstoffer enn den øvrige befolkningen. Slik er beregningene og vurderingene gjort VKM har laget to kostrådsscenarioer basert på mengder av ulike matvaregrupper, som er gitt i høringsutkastet eller som tilleggsinformasjon fra Helsedirektoratet underveis i arbeidet med rapporten. Eksempelvis inneholder det lave scenarioet 500 gram frukt og grønnsaker, mens det høye scenarioet inneholder 800 gram. Det lave scenarioet inneholder ikke egg, ost eller rødt kjøtt, mens høyt scenario inneholder ett egg om dagen, to osteskiver om dagen og 350 gram rødt kjøtt i uken. Begge scenarioene inneholder eksempelvis også 90 gram fullkorn per dag. Valget av matvarer fra matvaregruppene som er inkludert i scenarioene er basert på ordlyden i kostrådene, samt innsikt fra nasjonale kostholdsundersøkelser. For å vurdere sannsynligheten til om disse scenariene inneholder tilstrekkelig med næringsstoffer, har VKM vurdert dem opp mot næringsstoffanbefalingene.Beregning og vurdering av i hvilken grad høringsutkast til nye kostråd vil dekke behov og anbefalinger for næringsstofferacceptedVersionacceptedVersio
Screening Programme 2023
Get PDFThe 2023 Screening Programme aimed to investigate the presence of emerging environmental concerning substances 1) at so-called “hot spot” locations, and 2) in marine top predators. Part 1 covered emerging substances that were considered for EU regulation; persistent, mobile and toxic; identified as problematic (Sweden); and UV-stabilizers. Sampling sites were a wastewater treatment plant, indoor dust, agricultural soils, and consumer products. Part 2 covered substances found in the 2021 Screening Programme as well as selected through the LIfeAPEX project. Additionally, in part 2, several classical legacy contaminants were included. A unique sample set was assembled with different types of tissue from whales (killer whale, sperm whale, fin whale, humpback whale, white beaked dolphin, and harbor porpoise) and sharks (greenland shark, porbeagle shark, and spiny dogfish). Highlights from the results in part 1 covered a high detection frequency and concentrations of one phthalate (CAS 6422-86-2) and two UV-stabilizers (CAS 154702-15-5 and 103597-45-1). In part 2, only a small number of the emerging substances were identified, while many of the legacy substances were found at high levels.publishedVersio
Seafloor primary production in a changing Arctic Ocean
Get PDFPhytoplankton and sea ice algae are traditionally considered to be the main primary producers in the Arctic Ocean. In this Perspective, we explore the importance of benthic primary producers (BPPs) encompassing microalgae, macroalgae, and seagrasses, which represent a poorly quantified source of Arctic marine primary production. Despite scarce observations, models predict that BPPs are widespread, colonizing ~3 million km2 of the extensive Arctic coastal and shelf seas. Using a synthesis of published data and a novel model, we estimate that BPPs currently contribute ~77 Tg C y−1 of primary production to the Arctic, equivalent to ~20 to 35% of annual phytoplankton production. Macroalgae contribute ~43 Tg C y−1, seagrasses contribute ~23 Tg C y−1, and microalgae-dominated shelf habitats contribute ~11 to 16 Tg C y−1. Since 2003, the Arctic seafloor area exposed to sunlight has increased by ~47,000 km2 y−1, expanding the realm of BPPs in a warming Arctic. Increased macrophyte abundance and productivity is expected along Arctic coastlines with continued ocean warming and sea ice loss. However, microalgal benthic primary production has increased in only a few shelf regions despite substantial sea ice loss over the past 20 y, as higher solar irradiance in the ice-free ocean is counterbalanced by reduced water transparency. This suggests complex impacts of climate change on Arctic light availability and marine primary production. Despite significant knowledge gaps on Arctic BPPs, their widespread presence and obvious contribution to coastal and shelf ecosystem production call for further investigation and for their inclusion in Arctic ecosystem models and carbon budgets.publishedVersio
Analysis of uptake of tralopyril and transformation products in salmon exposed to tralopyril coated net pen
Get PDFThis report is performed on contract with Netkem AS, Norway. NetKem is a manufacturer of antifouling products for aquaculture nets. Experimental set up was discussed with researchers at Institute of Marine Research, Norway beforehand. The exposure experiment and sampling were performed by LetSea AS, Dønna, Norway. Letsea is a research centre for aquaculture. We thank the staff at LetSea AS for excellent performance and high-quality material.Analysis of uptake of tralopyril and transformation products in salmon exposed to tralopyril coated net penpublishedVersio
Exposure of Polycyclic Aromatic Hydrocarbons (PAHs) and Crude Oil to Atlantic Haddock (Melanogrammus aeglefinus): A Unique Snapshot of the Mercapturic Acid Pathway
Get PDFFish exposed to xenobiotics like petroleum-derived polycyclic aromatic hydrocarbons (PAHs) will immediately initiate detoxification systems through effective biotransformation reactions. Yet, there is a discrepancy between recognized metabolic pathways and the actual metabolites detected in fish following PAH exposure like oil pollution. To deepen our understanding of PAH detoxification, we conducted experiments exposing Atlantic haddock (Melanogrammus aeglefinus) to individual PAHs or complex oil mixtures. Bile extracts, analyzed by using an ion mobility quadrupole time-of-flight mass spectrometer, revealed novel metabolites associated with the mercapturic acid pathway. A dominant spectral feature recognized as PAH thiols set the basis for a screening strategy targeting (i) glutathione-, (ii) cysteinylglycine-, (iii) cysteine-, and (iv) mercapturic acid S-conjugates. Based on controlled single-exposure experiments, we constructed an interactive library of 33 metabolites originating from 8 PAHs (anthracene, phenanthrene, 1-methylphenanthrene, 1,4-dimethylphenanthrene, chrysene, benz[a]anthracene, benzo[a]pyrene, and dibenz[a,h]anthracene). By incorporation of the library in the analysis of samples from crude oil exposed fish, PAHs conjugated with glutathione and cysteinylglycine were uncovered. This qualitative study offers an exclusive glimpse into the rarely acknowledged mercapturic acid detoxification pathway in fish. Furthermore, this furnishes evidence that this metabolic pathway also succeeds for PAHs in complex pollution sources, a notable discovery not previously reported.publishedVersio
Atlantic salmon in chronic turbulence: Effects on growth, behaviour, welfare, and stress
Get PDFAn increasing number of aquaculture companies aim to relocate Atlantic salmon (Salmo salar) farms to offshore locations exposed to large wave action. However, the impact that this environment will have on the fish reared within remains unknown, raising questions about their coping ability and welfare. The purpose of this study was to address this knowledge gap and understand how Atlantic salmon respond to wave-induced turbulence. For 8 weeks, post-smolts were exposed to chronic turbulence created using specially designed wave-generating equipment. During the trial, feed intake, growth, behavioural conditioning, plasma biochemistry and welfare were monitored. At study end, swimming capacities were determined, and vertebral deformities were assessed in a sub-group of fish. Despite both control and turbulence groups doubling their weights, the turbulence group exhibited a 5% reduction in size. A drop- in appetite, 17% across the first five days, and deviant behaviour was observed for the first 3 weeks in the turbulence group. These disparities disappeared in the latter half of the trial, suggesting the fish acclimatized. Welfare scores, haematological parameters, critical swimming speeds and deformity prevalence remained similar across both groups, suggesting the fish were not impacted by chronic turbulence on a physical or physiological level. In conclusion, these findings demonstrate that Atlantic salmon is a robust species with the capacity to adapt to novel more chaotic environments without suffering substantial reductions in welfare or long-term production performance. This suggests that Atlantic salmon will be able to adapt and thrive in wave-exposed turbulent offshore farm environments.publishedVersio
Multi-isotopic composition of brown crab (Cancer pagurus) and seafloor sediment from a mine tailing sea disposal impacted fjord ecosystem
Get PDFSea disposal of mine tailings in fjord ecosystems is an important coastal management issue in Norway and occurs at the land-sea interface. Here we studied accumulation of heavy metals in brown crab (Cancer pagurus) and seafloor sediment from Jøssingfjord, Norway during 2018 to evaluate long-term, legacy pollution effects of coastal mine tailing sea disposal activities. Nickel and copper sediment pollution in the mine tailing sea disposal area was classified as moderate and severe, respectively, under Norwegian environmental quality standards, and highlights the persistent hazard and legacy impacts of heavy metals in these impacted fjord ecosystems. Mercury, zinc, and arsenic had stronger affinities to brown crab muscle likely due to the presence of thiols, and availability of metal binding sites. Our multi-isotopic composition data showed that lead isotopes were the most useful source apportionment tool for this fjord. Overall, our study highlights the importance and value of measuring several different heavy metals and multiple isotopic signatures in different crab organs and seafloor sediment to comprehensively evaluate fjord pollution and kinetic uptake dynamics. Brown crabs were suitable eco-indicators of benthic ecosystem heavy metal pollution in a fjord ecosystem still experiencing short- and long-term physical and chemical impacts from coastal mining sea disposal activities.publishedVersio