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Re-calibration of the MAGIC model with data from the National Lake Survey 2019. Results from phase 2
Get PDFProsjektleder: Øyvind KasteThe biogeochemical MAGIC model has been applied to the data from the 1995 and 2019 surveys of 1000 Norwegian lakes. The work is a follow-up of a modelling exercise that was done in 2022, with improved input data and with new deposition estimates generated from NILU’s deposition station network. The results indicated that the new deposition data from NILU gave slightly better simulated results (compared to the observed) than those with the deposition estimates from EMEP used in 2022. For future work we recommend that the calibrations to the 2019 data driven by the deposition data from NILU’s deposition station network are used.Norwegian Environment AgencypublishedVersio
Municipal Solid Waste Fly Ash-Derived Zeolites as Adsorbents for the Recovery of Nutrients and Heavy Metals—A Review
Get PDFThough fly ash from the incineration of municipal solid waste (MSW-FA) is considered hazardous waste, its huge and increasing volumes and potential value due to high concentrations of salts and heavy metals such as copper and zinc have attracted commercial interest in mining it for resources. The associated treatments used for extracting these resources may make it economically feasible to extract other constituents from the residuals, adding another potential pathway towards a zero-waste society. This review assesses the feasibility of using zeolites, synthesized from precursors extracted from MSW-FA, as sorbents for the recovery of nutrients (ammonium, nitrate, and phosphate) and heavy metals. It is possible to tailor the properties of the zeolites; however, the large variability in reported adsorption capacities and specificities, as well as the inherent heterogenic nature and variable composition and concentrations of most nutrient- or heavy metal-rich waste streams, make such tailoring challenging. A remaining important issue is the transfer of unwanted micropollutants from the MSW-FA or waste stream to the final products and the loss of surfactants from surfactant-modified zeolites during adsorption and/or desorption of nitrate and/or phosphate. Nonetheless, the recovery process is benefited by high concentrations of the target compounds and low concentrations of competing ions.publishedVersio
Freshwater Lacustrine Zooplankton and Microplastic: An Issue to Be Still Explored
Get PDFLakes are essentially interlinked to humans as they provide water for drinking, agriculture, industrial and domestic purposes. The upsurge of plastic usage, its persistence, and potential detrimental effects on organisms cause impacts on the trophic food web of freshwater ecosystems; this issue, however, still needs to be explored. Zooplankton worldwide is commonly studied as an indicator of environmental risk in aquatic ecosystems for several pollutants. The aim of the review is to link the existing knowledge of microplastic pollution in zooplankton to assess the potential risks linked to these organisms which are at the first level of the lacustrine trophic web. A database search was conducted through the main databases to gather the relevant literature over the course of time. The sensitivity of zooplankton organisms is evident from laboratory studies, whereas several knowledge gaps exist in the understanding of mechanisms causing toxicity. This review also highlights insufficient data on field studies hampering the understanding of the pollution extent in lakes, as well as unclear trends on ecosystem–level cascading effects of microplastics (MPs) and mechanisms of toxicity (especially in combination with other pollutants). Therefore, this review provides insight into understanding the overlooked issues of microplastic in lake ecosystems to gain an accurate ecological risk assessment.publishedVersio
Multiomics Point of Departure (moPOD) Modeling Supports an Adverse Outcome Pathway Network for Ionizing Radiation
Get PDFWhile adverse biological effects of acute high-dose ionizing radiation have been extensively investigated, knowledge on chronic low-dose effects is scarce. The aims of the present study were to identify hazards of low-dose ionizing radiation to Daphnia magna using multiomics dose–response modeling and to demonstrate the use of omics data to support an adverse outcome pathway (AOP) network development for ionizing radiation. Neonatal D. magna were exposed to γ radiation for 8 days. Transcriptomic analysis was performed after 4 and 8 days of exposure, whereas metabolomics and confirmative bioassays to support the omics analyses were conducted after 8 days of exposure. Benchmark doses (BMDs, 10% benchmark response) as points of departure (PODs) were estimated for both dose-responsive genes/metabolites and the enriched KEGG pathways. Relevant pathways derived using the BMD modeling and additional functional end points measured by the bioassays were overlaid with a previously published AOP network. The results showed that several molecular pathways were highly relevant to the known modes of action of γ radiation, including oxidative stress, DNA damage, mitochondrial dysfunction, protein degradation, and apoptosis. The functional assays showed increased oxidative stress and decreased mitochondrial membrane potential and ATP pool. Ranking of PODs at the pathway and functional levels showed that oxidative damage related functions had relatively low PODs, followed by DNA damage, energy metabolism, and apoptosis. These were supportive of causal events in the proposed AOP network. This approach yielded promising results and can potentially provide additional empirical evidence to support further AOP development for ionizing radiation.publishedVersio
Innføring i vannforvaltningen i Norge etter EU sitt vanndirektiv.
Get PDFProsjektleder: Gunnar SanderEU sitt vanndirektiv er et ambisiøst forsøk på å få en helhetlig forvaltning av alt vann, både ferskvann, grunnvann og kystvann. Målet er at vannet skal ha minst god økologisk og god kjemisk tilstand. Alle som bidrar til å påvirke vannets miljøtilstand eller har interesser knyttet til vann skal inviteres inn i en samordnet forvaltning som organiseres rundt nedbørsfelt og kyststrekninger. Dette bryter med de fleste administrative organiseringer. Norge har iverksatt vanndirektivet gjennom vannforskriften. Den definerer organiseringen av norsk vannforvaltning, oppgavene som skal løses og metodene som skal brukes. Arbeidet ledes fra staten gjennom ei departements- og ei direktoratsgruppe. Det sentrale samordnende nivået er vannregionene som koordineres av fylkeskommunene og som får bidrag fra lokal organisering i vannområder. De lager vannforvaltningsplaner som oppdateres hvert 6. år. Tiltaksprogrammet i planene skal sørge for at det blir gjennomført tiltak som gjenoppretter god miljøtilstand og beskytter mot forringelse. Sektormyndigheter og kommuner har imidlertid utstrakt kontroll over hva som blir iverksatt av tiltak. Vannforvaltningen skal være kunnskapsbasert og har bygget opp omfattende systemer for datalagring. Forskningen i Framsenteret kan bidra med utfyllende data, kunnskap om prosesser og effekter av menneskelige påvirkninger, bedre verktøy og modeller, samt kunnskap om hvordan forvaltningen fungerer.Framsenteret sine forskningsprogrammer C2C, CLEAN og CoastShift.publishedVersio
Metabolism Modeling in Rivers With Unsteady Flow Conditions and Transient Storage Zones
Get PDFWhole-stream metabolism characterizes energy and carbon transformations, thus providing an estimate of the food base and CO2 emission sources from streams and rivers. Metabolism models are generally implemented with a steady flow assumption that does not hold true for many systems with sub-daily flow variation, such as river sections downstream of dams. The steady flow assumption has confined metabolism estimation to a limited range of river environments, thus limiting our understanding about the influence of hydrology on biological production in rivers. Therefore, we couple a flow routing model with the two-station stream metabolism model to estimate metabolism under unsteady flow conditions in rivers. The model's applicability is further extended by including advection-dispersion processes to facilitate metabolism estimation in transient storage zones. Metabolism is estimated using two approaches: (a) an accounting approach similar to the conventional two-station method and (b) an inverse approach that estimates metabolism parameters using least squares minimization method. Both approaches are complementary since we use outputs of the accounting approach to constrain the inverse model parameters. The model application is demonstrated using a case study of an 11 km long stretch downstream of a hydropower plant in the River Otra in southern Norway. We present and test different formulations of the model to show that users can make an appropriate selection that best represents hydrology and solute transport mechanism in the river system of interest. The inclusion of unsteady flows and transient storage zones in the model unlocks new possibilities for studying metabolism controls in altered river ecosystems.publishedVersio
Innovative reference materials for method validation in microplastic analysis including interlaboratory comparison exercises
Get PDFReference materials (RMs) are vital tools in the validation of methods used to detect environmental pollutants. Microplastics, a relatively new environmental pollutant, require a variety of complex approaches to address their presence in environmental samples. Both interlaboratory comparison (ILC) studies and RMs are essential to support the validation of methods used in microplastic analysis. Presented here are results of quality assurance and quality control (QA/QC) performed on two types of candidate microplastic RMs: dissolvable gelatin capsules and soda tablets. These RMs have been used to support numerous international ILC studies in recent years (2019–2022). Dissolvable capsules containing polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyethylene (PE), and polystyrene (PS), in different size fractions from 50 to 1000 µm, were produced for one ILC study, obtaining relative standard deviation (RSD) from 0 to 24%. The larger size fraction allowed for manual addition of particles to the capsules, yielding 0% error and 100% recovery during QA/QC. Dissolvable capsules were replaced by soda tablets in subsequent ILC studies and recovery test exercises because they were found to be a more reliable carrier for microplastic RMs. Batches of soda tablets were produced containing different single and multiple polymer mixtures, i.e., PE, PET, PS, PVC, polypropylene (PP), and polycarbonate (PC), with RSD ranging from 8 to 21%. Lastly, soda tablets consisting of a mixture of PE, PVC, and PS (125–355 µm) were produced and used for recovery testing during pretreatment of environmental samples. These had an RSD of 9%. Results showed that soda tablets and capsules containing microplastics >50 µm could be produced with sufficient precision for internal recovery tests and external ILC studies. Further work is required to optimize this method for smaller microplastics (< 50 µm) because variation was found to be too large during QA/QC. Nevertheless, this approach represents a valuable solution addressing many of the challenges associated with validating microplastic analytical methods.publishedVersio
Microbial degradation dynamics of farmed kelp deposits from Saccharina latissima and Alaria esculenta
Get PDFSeaweed farming is a growing industry worldwide, and its sustainable management requires detailed knowledge about the environmental implications of detrital release. This study investigates benthic degradation of kelp detritus in defaunated mesocosms. The degradation dynamics were investigated over several weeks by resolving O2 and dissolved inorganic carbon (DIC) fluxes as a function of detritus amendments (0.15 g wet weight [WW] m-2 to 1 kg WW m-2), temperature (8 and 15°C), and presence of O2 for 2 commercially important kelp species: Saccharina latissima and Alaria esculenta. Kelp fragments were deposited in 2 different ways to simulate oxic and anoxic degradation: on the sediment surface (surface amendments) and just below the oxic surface sediment layer (subsurface amendments). All amendments resulted in high initial O2 consumption followed by an exponential decrease in O2 uptake over time. The degradation rates increased linearly with the amount of kelp added for both species and for both types of amendments. S. latissima expressed higher decay constants across all experiments and had a higher percentage turnover of carbon. In some instances, microbial priming apparently enabled enhanced degradation of pre-existing resilient sedimentary carbon. The absolute degradation rates of kelp were reduced in the absence of O2, and sulfate reduction resulted in gradual accumulation of iron sulfide. Lower ambient temperature reduced the benthic mineralization rate of both kelp species, particularly during the initial incubation stages. The current study demonstrates the importance of key variables for microbial kelp degradation in marine sediments and their dynamics—variables that should be carefully considered when assessing environmental implications of seaweed farming.publishedVersio
Rapport fra workshop med norske interessenter om overvåking av forsøpling
Get PDFProsjektleder: Jannike Falk-AnderssonDenne rapporten oppsummerer innspill fra deltagere under workshop holdt med norske interessenter på temaet «Overvåkning av forsøpling, med fokus på makroplast». Formålet med workshopen var å diskutere utfordringer og muligheter knyttet til å utvikle et helhetlig overvåkningsprogram for makrosøppel i Norge. Kartlegging av kunnskapsbehov identifiserte blant annet at det er viktig med overvåkningsdata som kan si noe om mengder og tilførsel av søppel, identifisere kilder, bidra til å identifisere målrettete tiltak, inkludert følge opp produsentansvar, samt måle effekten av tiltak. Disse kunnskapsbehovene er i noen grad dekket av data som hentes inn i dag på strandsøppel, men det er behov for å øke kvaliteten og mengden av data både i tid og rom.Norges ForskningsrådpublishedVersio
Contrasting long-term trends in juvenile abundance of a widespread cold-water salmonid along a latitudinal gradient: effects of climate, stream size and migration strategy
Get PDFA changing climate reshapes the range distribution of many organisms, and species with relatively low thermal optima, like many salmonids, are increasingly expected to face local population extinctions at lower latitudes. Understanding where and how fast these changes are happening is of pivotal importance for successful mitigation and conservation efforts. We used an extensive electrofishing database to explore temporal trends of juveniles of brown trout Salmo trutta in 218 locations from 174 Swedish streams, over the last 30 years (1991–2020). We hypothesized that 1) declines in abundance have occurred predominately in the warmer, southern regions, while increases have occurred in the colder, northern regions, 2) larger stream sizes may partly offset negative effects of climate, and 3) migrating and resident populations are affected differently by a warming climate. We found that abundance of brown trout juveniles generally declined in warmer regions especially in smaller streams (≤ 6 m wide), while the abundance increased in colder regions. In larger streams, negative effects of higher temperatures were seemingly buffered, as we found lower rates of decline or even positive trends. The rate of change (i.e. the slopes of the trends in abundance) was more pronounced towards the climate extremes, and was on average zero in regions with a normal annual air temperature (average temperature over 30 year period) around 5–6 °C. Warmer climate had stronger effects on migrating compared to resident populations, suggesting that climate-induced loss of stream connectivity could be an additional factor that hinders recruitment in anadromous populations in a changing climate. Considering predictions of increasing temperatures and frequency of summer droughts, management of cold-water salmonid populations should focus on conserving and restoring riparian vegetation, wetlands, climate and thermal refugia, and habitat integrity overall. Such measures may, however, not suffice for small streams at lower latitudes, unless hydrological connectivity is maintained.publishedVersio