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Undersøkelse av forurensede sedimenter i Sandvika, Holtekilen og Hundesundet i Bærum. Kartlegging og risikovurdering av forurenset sediment trinn 3
Get PDFProsjektleder: Sigurd ØxnevadNIVA har på oppdrag for Bærum kommune utført kartlegging av miljøgifter i sediment for et område utenfor Sandvika, i Holtekilen og i Hundesundet. Sedimentprøver er analysert for tungmetaller (arsen, bly, kadmium, kobber, krom, kvikksølv, nikkel og sink), polysykliske aromatiske hydrokarboner (PAH-forbindelser), polyklorerte bifenyler (PCB), perfluorerte alkylstoffer (PFAS) og tinnorganiske forbindelser. Det ble også gjort overvåking av utvalgte miljøgifter i vann ved analyse av passive prøvetakere, og det ble gjort analyser av utvalgte miljøgifter i fisk fanget i de tre områdene. De nye dataene for konsentrasjoner av miljøgifter i sediment, vann og fisk er brukt til å utføre en risikovurdering av forurenset sediment trinn 3. Hensikten med denne undersøkelsen har vært å skaffe mer detaljerte data om forurensningssituasjonen i sedimentene i Sandvika, Holtekilen og Hundesundet, og hvilken risiko de forurensede sedimentene utgjør. Den nye informasjonen om miljøtilstand og risiko skal gi bedre grunnlag for å bestemme om det skal gjøres tiltak mot forurensningen i sjøbunnen i disse områdene.Bærum kommunepublishedVersio
High aquatic macrophyte diversity in Norwegian lakes north of the Arctic Circle
Get PDF1. Aquatic macrophytes recolonised inland waters following the last glacial retreat. The resulting diversity and the variables influencing it remain largely unexplored north of the Arctic Circle, including possible effects of past colonisation routes. Our understanding of species diversity north of the Arctic Circle has also been hampered by a lack of control in sampling effort. 2. Here we use a newly assembled set of lake surveys from Norway to test: (1) whether regional richness (γ diversity) as well as turnover, net gain and loss (β diversity) of species differ between bioclimatic zones, latitudinal bands, and geographical regions; (2) how the environment and the spatial structure (e.g. dispersal constraints) may predict lake species richness (α diversity); and (3) how the changes in species β diversity between lakes are related to these environmental and spatial gradients. 3. We expected high species turnover with longitude, net species loss with latitude and higher species richness in north-east compared to mid Norway due to geographical dispersal barriers and past recolonisation routes. However, the regional species richness was similar across all geographical regions after correcting for sampling effort and spatial extent, with slightly lower richness in north Norway (−4%) and north-east Norway (−11%) than expected by the species area relationship. Species β diversity (both turnover and loss) was also surprisingly low between most areas. 4. Species richness per lake increased with lake area and temperature, showed a preferential peak at 10 μg/L total phosphorus, was sensitive to spatial structure, and largely indifferent to calcium (or alkalinity). In contrast, β diversity (mostly turnover) increased with differences in calcium, total phosphorus, and latitude, while not responding much to temperature and lake area. Species loss and gain between lakes were hardly related to any of the selected variables. 5. Overall, species richness (α, γ) was higher than expected north of the Arctic Circle mostly due to species turnover with little net loss. These patterns suggested good dispersal abilities by aquatic plants, after controlling for sampling efforts and spatial extent. Conservation of aquatic plants should not be driven by the delineation of terrestrial vegetation zones, but through an understanding of the variables affecting aquatic plant diversity. Finally, northern lakes may be increasingly important as reservoirs of macrophyte diversity under global warming.High aquatic macrophyte diversity in Norwegian lakes north of the Arctic CirclepublishedVersio
Modellering av avlastningsbehov for ulike delområder (forprosjekt)
Get PDFProsjektleder/Hovedforfatter James Edward SampleNIBIO-modellen JOVAest og NIVA-modellen TEOTIL har vært brukt i mange år for å simulere tilførsler av totalt nitrogen og fosfor på nasjonal skala i Norge. Modellene brukes til å støtte vannforvaltning, for eksempel ved å sammenligne simulerte tilførsler med målverdier. Denne rapporten beskriver de eksisterende modellene i detalj og foreslår oppdateringer og forbedringer for å gjøre modelleringsarbeidsflyten mer relevant for behovene til vannforvaltere. Foreslåtte endringer inkluderer: (i) oppdatering av alle komponenter i den eksisterende arbeidsflyten; (ii) å bruke modellen Agricat2 for å simulere jordbruksfosfor; (iii) simulering av underfraksjoner av totalt nitrogen og fosfor; (iv) tilsetning av suspendert sediment og organisk materiale som tilleggsparametere; og (v) å tilføre ytterligere punktkilder til næringsstoffer, slik som utslipp fra landbasert akvakultur.publishedVersio
Is Glacial Meltwater a Secondary Source of Legacy Contaminants to Arctic Coastal Food Webs?
Get PDFClimate change-driven increases in air and sea temperatures are rapidly thawing the Arctic cryosphere with potential for remobilization and accumulation of legacy persistent organic pollutants (POPs) in adjacent coastal food webs. Here, we present concentrations of selected POPs in zooplankton (spatially and seasonally), as well as zoobenthos and sculpin (spatially) from Isfjorden, Svalbard. Herbivorous zooplankton contaminant concentrations were highest in May [e.g., ∑polychlorinated biphenyls (8PCB); 4.43, 95% CI: 2.72–6.3 ng/g lipid weight], coinciding with the final stages of the spring phytoplankton bloom, and lowest in August (∑8PCB; 1.6, 95% CI: 1.29–1.92 ng/g lipid weight) when zooplankton lipid content was highest, and the fjord was heavily impacted by sediment-laden terrestrial inputs. Slightly increasing concentrations of α-hexachlorocyclohexane (α-HCH) in zooplankton from June (1.18, 95% CI: 1.06–1.29 ng/g lipid weight) to August (1.57, 95% CI: 1.44–1.71 ng/g lipid weight), alongside a higher percentage of α-HCH enantiomeric fractions closer to racemic ranges, indicate that glacial meltwater is a secondary source of α-HCH to fjord zooplankton in late summer. Except for α-HCH, terrestrial inputs were generally associated with reduced POP concentrations in zooplankton, suggesting that increased glacial melt is not likely to significantly increase exposure of legacy POPs in coastal fauna.publishedVersio
Nitrogen in surface waters: time trends and geographical patterns explained by deposition levels and catchment characteristics
Get PDFMain author Kari AustnesThe report presents a statistical analysis of controls (deposition, land cover, climate) on spatial variability and long-term trends (1992-2016) in surface water concentrations of nitrate (NO3) and carbon to nitrogen (C/N) ratios of dissolved organic matter (DOM) at the ICP Water sites in Europe and North America. Nitrogen (N) deposition has declined over large parts of Europe and North America. Surface water NO3 has decreased significantly at 46% of sites, increased at a few sites (4%) and has had no significant trend at the remaining sites. The C/N ratio of DOM has increased at 52% of the sites, decreased at 5% and has no trend at 43% of the sites. The greatest decline in surface water NO3 occurred at sites with high N deposition and high NO3 concentrations. The increase in C/N ratios of DOM is mainly related to increasing trends in total organic carbon (TOC) and seems largely unaffected by N deposition levels or trends. Data from most of the ICP Waters sites do not suggest that N saturation is occurring presently, but there is still a risk that climate change and ecosystem disturbances might cause higher N leaching in the future.publishedVersio
Bradalsmyra testsenter. Overvåkning av metallkonsentrasjoner i bekker og grunnvannsig i perioden 2004-2021.
Get PDFProsjektleder Asle ØkelsrudBradalsmyra er Nammo Raufoss AS sitt testsenter for utprøving av ny ammunisjon, etablerte serieprodukter, rakettmotorer og andre fremdriftssystemer. Området avvannes av Veltmannåa, og to mindre bekker. Vi fortsetter her rapportering av overvåkingen av metaller, som har pågått siden 1991. Prøvetaking foregår månedlig i den isfrie perioden. I 2021 var det overskridelser av gjeldende miljøkvalitetsstandard (EQS) for kobber og sink ved stasjon 8, som ligger nedstrøms stasjon 9 ved rakettstandplass. Vannforekomsten oppnår dermed ikke miljømålet om god økologisk tilstand. Det ble ikke observert overskridelser av EQS for de vannregionspesifikke stoffene ved stasjonene i de to andre utgående bekkene, hhv. stasjon 4 Veltmannåa og stasjon 7 nedenfor verkstedsområdet. Disse er derfor i «god økologisk tilstand». Det ble ikke observert overskridelser av EQS for de prioriterte stoffene bly, kadmium og nikkel i noen av de tre utgående bekker. Disse er dermed i «god kjemisk tilstand». Påvirkning av kjemisk tilstand nedstrøms feltet vurderes derfor som liten. Den månedlige overvåkningen har den fordelen at eventuelle økte utslipp kan stanses på et tidlig tidspunkt, og hindre negative effekter på biota nedstrøms testsenteret.publishedVersio
The Norwegian river monitoring programme 2020 – water quality status and trends
Get PDFRevidert versjon av rapport 7675-2021In the Norwegian River Monitoring Programme (in Norwegian: Elveovervåkingsprogrammet) 20 rivers along the Norwegian coastline are monitored for chemical and hydrological parameters. It is a continuation of the RID programme (Riverine inputs and direct discharges to Norwegian coastal waters) that started in 1990. This report presents the current status (2020) and long-term (1990-2020) water quality trends.publishedVersio
Levels of nitramines and nitrosamines in lake drinking water close to a CO2 capture plant: A modelling perspective
Get PDFWhile CO2 capture is considered a key climate change mitigation option, we must ensure that global implementation occurs without causing harm to the local environment and the human health. The most mature option for capture is using amines, which however, is associated with a risk of contaminating nearby drinking water sources with carcinogenic nitramines (NAs) and nitrosamines (NSAs). Here we present the first process-based simulation of NAs and NSAs in a catchment-lake system with the input of previously modelled atmospheric deposition rates. Considering full-scale CO2 capture at the Oslo waste incineration plant in Norway, future (∼10 y) levels in a nearby lake approach the national drinking water limit. We further quantified the effect of hydrological and biogeochemical processes and identified those with the highest sensitivity (NA biodegradation). The uncertainty of the results is presented by a probabilistic distribution (Monte Carlo analysis), incorporating variability in catchment, lake, and literature NA and NSA parameter values. This modelling tool allows for the site-specific assessment of the abovementioned risks related to amine-based CO2 capture and aspires to contribute to the sound evaluation of costly amine emission reduction measures.publishedVersio
Tiltaksorientert overvåking i Håøyfjorden i 2021 for Chemring Nobel AS
Get PDFProsjektleder Gunhild BorgersenNIVA har gjennomført tiltaksorientert overvåking i henhold til vannforskriften i Håøyfjorden ved Sætre i Asker kommune i 2020/21, på oppdrag for Chemring Nobel AS. Hensikten med overvåkingen har vært å identifisere hvorvidt bedriftens utslipp påvirker vannforekomstens økologiske tilstand. Overvåkingen omfattet undersøkelse av de biologiske kvalitetselementene makroalger (ved nedre voksegrense), bløtbunnsfauna og planteplankton (ved klorofyll a), og de fysisk-kjemiske kvalitetselementene næringssalter, siktdyp og oksygen i bunnvann. Den økologiske tilstanden for makroalger var «god» på tre stasjoner og «moderat» på én stasjon. Én stasjon kunne ikke klassifiseres. For bløtbunnsfauna var den økologiske tilstanden «god» på to stasjoner og «moderat» på to stasjoner. Det var høyt innhold av totalt organisk karbon og totalt nitrogen i sedimentet på de fire bunnfaunastasjonene. Tilstanden for planteplankton ble klassifisert til «dårlig», basert på høye verdier av klorofyll a i 5 og 10 m dyp. Tilstanden for siktdyp var også «dårlig». Tilstanden for næringssalter ble vurdert til «svært god» for sommersesongen, men «dårlig» for vintersesongen basert på høye verdier for nitrat og nitritt.publishedVersio
Highly Productive Ice Algal Mats in Arctic Melt Ponds: Primary Production and Carbon Turnover
Get PDFArctic summer sea ice extent is decreasing and thinning, forming melt ponds that cover more than 50% of the sea ice area during the peak of the melting season. Despite of this, ice algal communities in melt ponds are understudied and so are their contribution to the Arctic Ocean primary production and carbon turnover. While melt ponds have been considered as low productive, recent studies suggest that accumulated ice algal potentially facilitate high and yet overlooked rates of carbon turnover. Here we report on ice algal communities forming dense mats not previously described, collected from melt ponds in the northern Barents Sea in July. We document on distinct layered and brown colored mats with high carbon assimilation and net primary production rates compared to ice algal communities and aggregates, in fact comparable to benthic microalgae at temperate tidal flats. Rates of gross and net primary production, as well as community respiration rates were obtained from oxygen micro profiling, and carbon assimilation calculations were supported by 14C incubations, pigment analysis and light microscopy examinations. The melt pond algal mats consisted of distinct colored layers and differed from aggregates with a consisted layered structure. We accordingly propose the term melt pond algal mats, and further speculate that these dense ice algal mats may provide an important yet overlooked source of organic carbon in the Arctic food-web. A foodweb component likely very sensitive to climate driven changes in the Arctic Ocean and pan-Arctic seas.publishedVersio