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Evaluering av bekkeåpningsprosjekter med naturbaserte løsninger i Alnas nedbørsfelt
Get PDFProsjektleder: Ingrid NesheimPå nasjonalt nivå, i Nasjonal strategi for restaurering av vassdrag 2021 – 2030, er det en tydelig ambisjon om å gjenåpne urbane lukkede bekke- og elvestrekninger. I Oslo kommune, er det en like tydelig politisk målsetning å gjenåpne bekke- og elvestrekninger der dette er mulig. Denne rapporten har som mål å øke kunnskapen om bekkeåpninger og tilknyttede prosesser for måloppnåelse. Tre ulike bekkeåpningsprosjekter, Lindebergbekken, Julsbergbekken og Bakåsbekken i Alnas nedbørfelt ble studert. Evalueringen har vurdert i hvilken grad ulike mål, deriblant FNs bærekraftsmål 6 og 15, Aichi‐mål 15 og forpliktelser etter EUs vanndirektiv ble tatt i betraktning i planleggingsprosessene, og i forbindelse med gjennomføring av bekkeåpningen. Rapporten presenterer videre IUCNs globale standard for naturbaserte løsninger og diskuterer relevansen av dette rammeverket for Oslo kommunes styringsdokument for bekkeåpningsprosjekter.Miljødirektoratet, finansiering fra VannmiljøtiltakpublishedVersio
Utredninger av tungmetallutslipp til Vefsnfjorden
Get PDFProsjektleder: Andre StaalstrømI denne rapporten beskrives modellering av tungmetaller i Vefsnfjorden med modellverktøyet Sedflex. Ser man på tilførsel i mengde per år, så dominerer Vefsna, som er den helt klart største kilden til tungmetaller til Vefsnfjorden. Ser man derimot på konsentrasjon i utslippet har avrenning fra deponiet ved Rynes svært mye høyere verdier enn de andre utslippene. Utslippet av kvikksølv fra deponiet påvirker konsentrasjonen i hele Vefsnfjorden i stor grad. Konsentrasjonen av kvikksølv i vannsøylen kan reduseres med hele 15 % og over 10 % i sedimentene i hele fjorden innenfor Rynes om avrenningen fra deponiet ble fjernet. Basret på modellresultatene så konkluderes det med at utslippet fra Alcoa Mosjøen påvirker metallkonsentrasjon i sediment og vannmassene i Vefsnfjorden i liten grad sammenlignet med tilførsel fra Vefsna.Alcoa MosjøenpublishedVersio
Resipientundersøkelse i forbindelse med utslipp av kommunalt avløpsvann fra Huseby renseanlegg, 2022-2023
Get PDFProsjektleder: Hilde Cecilie TrannumDet er utført en resipientundersøkelse i forbindelse med utslipp av kommunalt avløpsvann fra Huseby renseanlegg i Farsund kommune. Miljøtilstanden er klassifisert basert på kravene i vannforskriften. Undersøkelsen omfattet klorofyll, næringssalter, siktdyp og oksygen i vannmassene, samt makroalger og bløtbunnsfauna. Begge de undersøkte vannforekomstene oppnådde tilstandsklasse «god» basert på dataene innsamlet i prosjektet. Fordi utslippet er lokalisert i et åpent og strømrikt område, synes det å være en rask fortynning av avløpsvannet. Det var lite klorofyll a i vannmassene, tilsvarende «svært god» tilstand. Videre var de omkringliggende makroalgesamfunnene friske og med tilstand opp mot «svært god». Også bløtbunnsfaunaen oppnådde en tilstand på minst «god», men stasjonen nærmest utslippet hadde adskillig lavere tilstandsverdi enn de øvrige. Det var forhøyet mengde organisk materiale i sedimentet i hele området, og spesielt på stasjonen nærmest utslippet. Det ble videre registrert spor av avløpsvann i bunnvannet i en av vannprøvene. Det anbefales at videre overvåking gjøres samlet for de ulike utslippene i resipienten for å følge med på at resipientens bæreevne ikke overskrides.Farsund kommunepublishedVersio
Assessment of the risk to Norwegian biodiversity from private import and keeping of Northern Cardinal. Scientific Opinion of the Panel on Biodiversity of the Norwegian Scientific Committee for Food and Environment
No full textVKM has evaluated the risk to biodiversity from allowing private import and keeping of the Northern Cardinal as a caged bird in Norway, for birds acquired through the bird trade. VKM has reviewed the invasion ecology of non-native birds in general and of the Northern Cardinal specifically. The assessment includes evaluation of various mechanisms that invasive birds generally have a negative impact through, and includes competition, hybridization, spread of pathogens and interactions with other alien species in Norway. VKM has also evaluated two different scenarios establishment and how climate change can influence both the negative impact and the likelihood of establishment. Overall, VKM finds that there is low risk in regards negative effects on biodiversity in Norway in regard to import and keeping of the Northern Cardinal.publishedVersio
Resultater fra overvåking av legemidler i avløpsvann fra et sykehus og gjennom et avløpsrenseanlegg – tilstedeværelse og miljørisiko, 2019-2022
Get PDFLegemiddelutslipp via avløpsvann fra sykehus kan forårsake negative miljøeffekter. I denne største norske studien siden 2007 undersøkte vi legemidler i påslipp fra sykehus til kommunalt avløpsnett, og i innløp og renset utslipp ved mot- tagende avløpsrenseanlegg. Vi inkluderte 157 legemidler. For åtte legemidler utgjorde tilførselen fra sykehuset 10-41% av totalmengden tilført renseanlegget. Disse brukes hovedsakelig i syke- hus (røntgenkontrastmidler, bedøvelsesmidler, visse antibiotikatyper). En enkel risikovurdering av utløpskonsentrasjonene fra avløpsrense- anlegget viste at de kvinnelige kjønnshormoner og legemidler østron og østradiol, representerte den største miljørisikoen. Risikokvotienten (RQ) for det betennelsesdempende midlet diklofenak og antibiotikatypene ciprofloksacin, azitromycin og sulfametoksasol var større enn 1, som betyr at negative effekter i miljøet ikke kan utelukkes. Manglende toksisitetsstudier av flere legemidler betyr at trygge miljøkonsentrasjoner ikke er ut- ledet. Flere studier av sykehusenes bidrag til mulige negative miljøeffekter i resipienten trengs for å gi informasjon om hvorvidt imple- mentering av punktrensing av påslippet fra sykehus er formålstjenlig.publishedVersio
Changes in Nutrient Concentration Resulting From Floods and Their Impact on the Estuary–Sea Continuum
No full textEvaluating the contribution of rivers to coastal seas in the Earth system and accurately predicting marine environmental responses to climate change are crucial for mitigating and addressing future natural disasters, especially those related to extreme hydrological events, such as fluvial floods. The Changjiang (Yangtze) River Estuary (CRE) and the East China Sea continuum, known for high environmental stress, complex marine dynamic processes, and frequent flood events, were selected to determine the compound impacts of a severe flood that persisted for the whole of July 2017. We conducted three cruise surveys before and after this flood event. Our surveys revealed that the phosphate concentration in the channel of the CRE declined from 2 to <1 μM during the flood, while the nitrate concentration remained stable. We applied a coupled physical-biogeochemical model to determine the spatio-temporal influence of floodwater (freshwater from upstream during flood events). During the initial rising discharge stage, surface phytoplankton blooms triggered by enhanced stratification consumed phosphate and significantly increased the N:P ratio in the sea. The ratio was restored as the blooms diminished, but remained elevated due to lower phosphate floodwater in the northeastward area within the low-salinity river plume. Model experiments also showed that phytoplankton biomass and N:P ratio in the flood plume region were sensitive to the riverine phosphate concentration inputs during the flood event.acceptedVersio
Plastic bans in India – Addressing the socio-economic and environmental complexities
Get PDFAs one of the flagship amendments to the Plastic Waste Management (PWM) Rules, 2021, the pan-Indian ban on a group of single-use plastic products (SUPPs) introduced in mid-2022 provided a departure point towards more progressive plastic waste legislation. The amendments have mostly been welcomed, yet challenges persist to facilitate its implementation, assess potential environmental impacts of alternative materials, and socio-economic concerns raised by various stakeholders. Considering the recent amendments to the PWM Rules, we critically engage with and highlight key considerations and prevailing challenges with regards to phasing out SUPPs. We argue that to shape sustainable solutions that reduce plastic pollution, uncertainties related to the environmental fate of SUPP alternatives need to be better understood, whilst recognising and accounting for broader socio-economic impacts of SUPP bans, including industry concerns, impacts on socio-economically disadvantaged communities, and the informal recycling sector. A stronger knowledge base on these aspects can mitigate negative social and environmental externalities, including potentially harmful consequences of ambitious plastic pollution reduction measures.publishedVersio
Intercomparison 2337: pH, Conductivity, Alkalinity, NO3-N, Cl, SO4, Ca, Mg, Na, K, TOC, Tot-P, Tot-N, Al, Fe, Mn, Cd, Pb, Cu, Ni, and Zn.
Get PDFProsjektleder: Tina BryntesenTwenty laboratories from fifteen countries accepted the invitation to join the ICP Waters chemical intercomparison. Two sets of samples were prepared and distributed to the participants: one for the determination of ions and one for metals. This year, acceptance rates were based on the Z’-scores obtained by the participants. In general, acceptance rates were high for all parameters. General trends in the choice of techniques continue to shift towards plasma from atomic absorption, and to mass detection from ionic emission. This is especially promising for the determination of metals at low levels.Norwegian Ministry of Climate and Environment; United Nations Economic Commission for Europe (UNECE)publishedVersio
Lake browning counteracts cyanobacteria responses to nutrients: Evidence from phytoplankton dynamics in large enclosure experiments and comprehensive observational data
Get PDFLakes worldwide are affected by multiple stressors, including climate change. This includes massive loading of both nutrients and humic substances to lakes during extreme weather events, which also may disrupt thermal stratification. Since multi-stressor effects vary widely in space and time, their combined ecological impacts remain difficult to predict. Therefore, we combined two consecutive large enclosure experiments with a comprehensive time-series and a broad-scale field survey to unravel the combined effects of storm-induced lake browning, nutrient enrichment and deep mixing on phytoplankton communities, focusing particularly on potentially toxic cyanobacterial blooms. The experimental results revealed that browning counteracted the stimulating effect of nutrients on phytoplankton and caused a shift from phototrophic cyanobacteria and chlorophytes to mixotrophic cryptophytes. Light limitation by browning was identified as the likely mechanism underlying this response. Deep-mixing increased microcystin concentrations in clear nutrient-enriched enclosures, caused by upwelling of a metalimnetic Planktothrix rubescens population. Monitoring data from a 25-year time-series of a eutrophic lake and from 588 northern European lakes corroborate the experimental results: Browning suppresses cyanobacteria in terms of both biovolume and proportion of the total phytoplankton biovolume. Both the experimental and observational results indicated a lower total phosphorus threshold for cyanobacterial bloom development in clearwater lakes (10–20 μg P L−1) than in humic lakes (20–30 μg P L−1). This finding provides management guidance for lakes receiving more nutrients and humic substances due to more frequent extreme weather events.publishedVersio
Surface microplastics in the Kara Sea: from the Kara Gate to the 83°N
Get PDFDespite ongoing research into microplastics pollution in the Arctic Ocean, the region remains underexplored. In the Eurasian Arctic studies mainly focus on the Barents Sea, while there are only limited and variable data from few stations in the Kara Sea. The study aims to perform an extensive survey of microplastics floating on the sea surface in the Kara Sea. The sampling throughout the Kara Sea was carried out using a neuston net in the August 2021 starting from the Kara Gate strait, reaching 83N latitude and ending in the north-eastern part of the Barents Sea along the border with the Kara Sea. Average abundance of microplastics was 0.124 ± 0.383 items/m3 in the Kara Sea. The Kara Gate exhibited the highest abundance of microplastics (0.93 ± 0.73 items/m3), suggesting that it is an important source of the microplastics pollution of the Kara Sea. The results suggest that the Ob and Yenisey rivers do not substantially contribute to the microplastic pollution of the Kara Sea due to significantly lower concentrations in the river plume water (0.008 ± 0.009 items/m3) compared to the other regions of the Kara Sea. Further, the river plume differs in chemical composition of microplastics dominated by expanded polystyrene (EPS) particles (52%) in contrast to other regions where the predominant polymer is polyethylene (PE) (64-77%). The study highlights the potential of the Kara Sea to accumulate the microplastics due to its semi-enclosed nature and complex interaction between inflow of waters originating from the North Atlantic and Ob-Yenisey river plume.publishedVersio