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The marine methane cycle in the Canadian Arctic Archipelago during summer
Get PDFIn the Arctic Ocean, methane concentrations surpassing global averages are prevalent, especially along sub-Arctic and Arctic continental shelf margins. Despite elevated dissolved methane levels, the Arctic Ocean exhibits minimal methane fluxes to the atmosphere, indicating a potential role of water column oxidation in methane processing. During the Northwest Passage Project in the summer of 2019, we integrated thermohaline, chemical, and biological data with in-situ and in-vitro methane data in Canadian Arctic Archipelago (CAA) waters. Elevated in-situ dissolved methane was prominent in near-surface Pacific waters (between 2 and 7 m), particularly in meltwater regions, with av. concentrations of 5.8 ± 2.5 nM within the upper 30m. While methane oxidation constants were generally low (av. 0.006 ± 0.002 d−1), surface waters in Wellington Channel and Croker Bay exhibited higher rates (av. 0.01 ± 0.0004 d−1), associated with Pacific-origin microbial taxa like Oleispira and Aurantivirga. Deeper layers (>200 m) displayed lower methane concentrations (av. 3.1 ± 1.1 nM) and oxidation rates (av. 0.005 ± 0.001 d−1). Sea ice showed elevated dissolved methane concentrations (av. 9.2 ± 5 nM). Waters in the western CAA exhibited a 25% increase in methane concentrations compared to ice-free areas. The overall picture suggested supersaturation of in-situ methane in shallow waters (between 2 and 50 m), coupled with faster oxidation rates in meltwater and Pacific dominant layers, suggesting rapid seasonal cycling of methane and prevention of the methane migration into the atmosphere.publishedVersio
Microcystin profiles in European noble crayfish Astacus astacus and water in Lake Steinsfjorden, Norway
Get PDFLake Steinsfjorden, an important noble crayfish (Astacus astacus) habitat, is often affected by blooms of Planktothrix spp. that produce microcystins (MCs). A poor correlation between MCs by ELISA in the water and in crayfish tissue in a study in 2015 prompted further investigation by LC–HRMS. LC–HRMS analyses of filters from water samples and on selected crayfish tissue extracts from the 2015 study revealed the presence of known and previously unreported MCs. Crayfish samples from May and June 2015 were dominated by MCs from the Planktothrix bloom, whereas in September novel MCs that appeared to be metabolites of MC-LR were dominant, even though neither these nor MC-LR were detected in the water in 2015. A water sample from October 2016 also showed MCs typical of Planktothrix (i.e., [d-Asp3]- and [d-Asp3,Dhb7]MC-RR and -LR), but low levels of MC-RR and MC-LR were detected in the lake water for the first time. In late summer and autumn, the MC profiles of crayfish were dominated by the homonorvaline (Hnv) variant MC-LHnv, a putative metabolite of MC-LR. Taken together, ELISA, LC–HRMS and previous PCR analyses showed that although Planktothrix was part of the crayfish diet, it was not the sole source of MCs in the crayfish. Possibly, crayfish in Lake Steinsfjorden may be ingesting MCs from benthic cyanobacteria or from contaminated prey. Therefore, information on the cyanobacterial or MC content in the water column cannot safely be used to make predictions about MC concentrations in the crayfish in Lake Steinsfjorden. Interestingly, the results also show that targeted LC–MS analysis of the crayfish would at times have underestimated their MC content by nearly an order of magnitude, even if all previously reported MC variants had been included in the analysis.publishedVersio
Klorbehandling i Driva og Litldalselva 2023 – Andre behandlingsår
Get PDFProsjektleder: Anders Gjørwad HagenI august 2023 ble den andre av to kjemiske behandlinger gjennomført mot lakseparasitten Gyrodactylus salaris i Drivaregionen. I de to elvene Driva og Litldalselva ble kloramin brukt som hovedkjemikalium. Klorbehandlingene ble gjennomført av et samarbeid mellom NIVA og NINA i henhold til kontrakt med Veterinærinstituttet som overordnet oppdragsgiver. I denne rapporten oppsummeres metodikk og resultater fra klorbehandlingen. Det ble gjort jevnlige målinger for å følge opp effekten av alle små og store doseringspunkter. I hovedelva viste analyse av disse prøvene at det generelt ble oppnådd en samlet behandlingseffekt på mer enn 90 mikrogramdøgn for alle stasjoner. I sidebekkene var det én av 188 stasjoner som ikke nådde målet på 90 mikrogramdøgn. Sannsynligheten for at det skal ha overlevd G. salaris i dette området høyt oppe i Litldalselva er imidlertid ansett som svært liten. Basert på funn fra behandlingen i 2022 ble behandlingen i 2023 utvidet, og dedikert personell ble allokert til å gjennomføre kritiske undersøkelser. Ved 34 punkter ble det gjort ett eller flere tiltak for å bedre behandlingen, og hvor det også ble gjort flere undersøkelser i etterkant for å vurdere effekten av tiltaket. Behandlingen var totalt sett vellykket, særlig gitt de vannføringsmessige utfordringene i forbindelse med ekstremværet «Hans».Veterinærinstituttet i TrondheimpublishedVersio
Language matters for biodiversity
Get PDFLanguage is central to the way people learn about the natural world. A salient concern of the biodiversity conservation arena has been to understand how language can be employed by scientists to communicate knowledge to nonexpert audiences and build ecological literacy. The use of analogy and narrative by scientists are prominent techniques. In this article, we consider how these two modes of language-based reasoning extend into ordinary conversational language use by the public, specifically when articulating everyday understanding and experiences of biodiversity. Drawing on a process of public engagement in a UK woodland environment, a typological framework based on principles of analogical and narrative reasoning is developed to characterize the precise character of processes of everyday biodiversity sense making. The implications of the framework are discussed in the context of future biodiversity research, particularly its participatory and educational dimensions.publishedVersio
Resipientovervåking av utslipp fra Elstrøm renseanlegg, Skien, i 2023
Get PDFProsjektleder: Camilla Hedlund Corneliussen HagmanPå oppdrag fra Skien kommune har NIVA laget et overvåkingsprogram for 2022-2024 for å møte kravene i utslippstillatelsen til Elstrøm renseanlegg, som har neddykket utslipp til Farelva. Overvåkingen i 2023 foregikk i Farelva, Falkumelva, Hjellevannet og Skienselva, og omfattet undersøkelser ved to referansestasjoner oppstrøms utslippet, to antatt påvirkede stasjoner samt en stasjon nedstrøms i større avstand fra utslippet. Alle stasjonene ble undersøkt for vannkvalitet, to stasjoner ble undersøkt for bunndyr, og den oppdemmede innsjøen Hjellevannet ble undersøkt for planteplankton og fysiske forhold. Med hensyn til vannkvalitet og planteplankton viste undersøkelsene ingen betydelige forskjeller mellom referansestasjonene og øvrige stasjoner, og alle hadde svært god økologisk tilstand. Dessverre var det uegnede fysiske forhold for bunndyr, spesielt ved den antatt påvirkede stasjonen, hvor det var svært dårlig økologisk tilstand basert på bunndyr. Dette gjør det umulig å konkludere med noen årsak til den dårlige tilstanden, da det kan være knyttet til påvirkning fra utslippet, eller like gjerne være mangel på egnet bunndyrhabitat. Det antas derfor at ikke Farelva, Hjellevannet eller Skienselva er påvirket i stor grad av utslippet til Elstrøm renseanlegg.Skien kommunepublishedVersio
A model for community-driven development of best practices: the Ocean Observatories Initiative Biogeochemical Sensor Data Best Practices and User Guide
Get PDFThe field of oceanography is transitioning from data-poor to data-rich, thanks in part to increased deployment of in-situ platforms and sensors, such as those that instrument the US-funded Ocean Observatories Initiative (OOI). However, generating science-ready data products from these sensors, particularly those making biogeochemical measurements, often requires extensive end-user calibration and validation procedures, which can present a significant barrier. Openly available community-developed and -vetted Best Practices contribute to overcoming such barriers, but collaboratively developing user-friendly Best Practices can be challenging. Here we describe the process undertaken by the NSF-funded OOI Biogeochemical Sensor Data Working Group to develop Best Practices for creating science-ready biogeochemical data products from OOI data, culminating in the publication of the GOOS-endorsed OOI Biogeochemical Sensor Data Best Practices and User Guide. For Best Practices related to ocean observatories, engaging observatory staff is crucial, but having a “user-defined” process ensures the final product addresses user needs. Our process prioritized bringing together a diverse team and creating an inclusive environment where all participants could effectively contribute. Incorporating the perspectives of a wide range of experts and prospective end users through an iterative review process that included “Beta Testers’’ enabled us to produce a final product that combines technical information with a user-friendly structure that illustrates data analysis pipelines via flowcharts and worked examples accompanied by pseudo-code. Our process and its impact on improving the accessibility and utility of the end product provides a roadmap for other groups undertaking similar community-driven activities to develop and disseminate new Ocean Best Practices.publishedVersio
Sammenlignende laboratorieprøving (SLP) – Industriavløpsvann SLP 2464
Get PDFProsjektleder Tina BryntesenVed en sammenlignende laboratorieprøving (SLP) arrangert i februar – mars 2024 deltok 63 laboratorier i bestemmelse av pH, suspendert stoff (tørrstoff og gløderest), sum organisk stoff (biokjemisk oksygenforbruk, kjemisk oksygenforbruk, totalt organisk karbon), totalfosfor, totalnitrogen og tolv metaller i syntetiske vannprøver. Ved denne SLPen, som har sitt utgangspunkt i Miljødirektoratets og fylkesmennenes kontroll med industriutslipp, er 92 % av resultatene ansett som akseptable. Andelen er noe høyere enn tidligere år, da resultatene i år vurderes individuelt der det tidligere ble vurdert parvis. De fleste parameterne viste en kvalitet som var sammenlignbar med de seneste SLPer.Norsk institutt for vannforskningpublishedVersio
Strategy towards producing relevant and reliable data for the hazard assessment of micro- and nanoplastics in agricultural soils
Get PDFMicro- and nanoplastics (MNPs) are widespread emerging contaminants with many potential direct and indirect effects on soil ecosystems. Ecological soil MNP hazard assessment is thus crucial for a proper risk assessment and the development of environmental protection regulations. However, current hazard assessment testing approaches are hampered by the absence of guidelines, harmonization, and standard reference materials. This article discusses the need for improving testing approaches and provides specific recommendations to increase the relevance and reliability of ecotoxicity data. Our recommendations focus on environmentally relevant experimental designs, guidelines for MNP test materials selection and characterization, analysis of MNPs and additives in soil and biota, and a proposal for relevant soil physicochemical properties to be assessed during ecotoxicity testing. This article brings novelty to the field of ecological hazard assessment of MNPs in soil by providing specific recommendations much needed in this field.publishedVersio
Comparing likely effectiveness of urban Nature-based Solutions worldwide: The example of riparian tree planting and water quality
Get PDFAmongst a spectrum of benefits, Nature-based Solutions (NBS) are increasingly being advocated as improving the quality of aquatic environments in urban areas. Of these, a widely adopted measure is tree planting. Yet, because of the local complexities and spatial variability of urban hydrological response, it is difficult to predict to what extent improvements in water quality will arise. To overcome this barrier, a standardised approach to process-based model simulation of urban river quality is described (QUESTOR-YARDSTICK (QUESTOR-YS)). The approach eliminates the influence of point sources of pollution and harmonises the way in which river hydrodynamics and contributory catchment size are represented. Thereby, it focuses on differences in water quality between cities due solely to climate, river discharge and urban diffuse nutrient pollution factors. The relative sensitivity to NBS establishment between urban water bodies in different cities anywhere across the world can also potentially be quantified. The method can be readily extended to include wastewater effluents. The validity of the approach is demonstrated for a small river in Birmingham, UK; and thence demonstrated for the case of 10 km of riparian tree planting in Birmingham, Oslo (Norway) and Aarhus (Denmark). Modelling suggests that riparian tree planting can substantially improve water quality in each example city for three key indicators of water quality in sensitive summer conditions (water temperature, chlorophyll-a and dissolved oxygen). Results show the level of benefit achievable in response to a fixed amount of planting will depend on the existing level of riparian tree occupancy.publishedVersio
Unravelling large-scale patterns and drivers of biodiversity in dry rivers
Get PDFMore than half of the world’s rivers dry up periodically, but our understanding of the biological communities in dry riverbeds remains limited. Specifically, the roles of dispersal, environmental filtering and biotic interactions in driving biodiversity in dry rivers are poorly understood. Here, we conduct a large-scale coordinated survey of patterns and drivers of biodiversity in dry riverbeds. We focus on eight major taxa, including microorganisms, invertebrates and plants: Algae, Archaea, Bacteria, Fungi, Protozoa, Arthropods, Nematodes and Streptophyta. We use environmental DNA metabarcoding to assess biodiversity in dry sediments collected over a 1-year period from 84 non-perennial rivers across 19 countries on four continents. Both direct factors, such as nutrient and carbon availability, and indirect factors such as climate influence the local biodiversity of most taxa. Limited resource availability and prolonged dry phases favor oligotrophic microbial taxa. Co-variation among taxa, particularly Bacteria, Fungi, Algae and Protozoa, explain more spatial variation in community composition than dispersal or environmental gradients. This finding suggests that biotic interactions or unmeasured ecological and evolutionary factors may strongly influence communities during dry phases, altering biodiversity responses to global changes.publishedVersio