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Drammen Fjernvarme: Nytt inntak og utslipp av driftsvann ved Brakerøya.
Get PDFProsjektleder Lars GolmenDrammen fjernvarme etablerte i 2010 et anlegg på Brakerøya for bruk av fjordvann til varming/kjøling av bygg på land. Vanninntaket er på 30 m dyp og utløpet på 13 m dyp i munningen av Drammenselva. Anlegget har teknisk sett fungert tilfredsstillende og det har ikke vært rapportert om problemer av miljømessig karakter. Det er nå planer om å doble kapasiteten i anlegget. Det vil medføre legging av nye ledninger langs bunnen og etablering av nytt inntak- og utløp. Vannforbruket vil dobles. Vannet vil oppvarmes inntil 9oC på varme dager og ellers avkjøles inntil 4 oC før det slippes ut. NIVA har på oppdrag fra Norsk Energi gjort miljømessige beregninger for et utvidet anlegg. Utslippsvannet vil synke og innlagres og spres i dybder rundt 14-16 meter. Overflatelaget i elvemunningen vil sannsynligvis ikke bli påvirket. Forutsatt at eksisterende og nytt utløp separeres med minst 50 meters avstand, er det ikke forventet interferens og sammenblanding av de to utløpsstrålene. På varme dager om sommeren vil anlegget tilføre fjorden inntil 25 MW varme. Ellers gjennom året vil inntil 23 MW varme tas fra fjorden. Sammenliknet med varmefluksen fra Drammenselva og lufta og fra strømninger ellers i fjorden blir dette normalt et lite bidrag. Inntaksvannet kan ha forhøyede næringssaltkonsentrasjoner og lavt oksygeninnhold. Utslippene vil også kunne påvirke bunnforholdene nær utløpene.publishedVersio
Potensial for restaurering og reintroduksjon av ålegrasenger i Oslofjorden, og mulighetene dette kan gi for klimatilpasning, karbonopptak og lagring
Get PDFProsjektleder Kristina Øie KvileÅlegrasenger er en viktig naturtype som huser et rikt biologisk mangfold og bidrar med en rekke økosystemtjenester, inkludert opptak og lagring av CO2. Klimaetaten i Oslo kommune ønsket en utredning av kunnskapsgrunnlaget og kartlegging av muligheter for restaurering eller reintroduksjon av ålegrasenger i sine sjøområder, og hvordan dette vil påvirke karbonopptak og klimatilpasning i Oslofjorden. I denne rapporten presenteres gjeldende kunnskap om ålegrasenger og deres økosystemtjenester og rolle for karbonopptak og klimatilpasning. Trusler mot ålegrasenger og hvordan restaurering av ålegrasenger kan motvirke de negative trendene, er også vurdert, med fokus på kystområdene innenfor Oslo kommunes grenser. Relevante lover og regler i forbindelse med restaurering blir også diskutert. I oktober 2021 gjennomførte NIVA en befaring for å undersøke relevante områder for restaurering, som er presentert i denne rapporten. En detaljert beskrivelse av hvordan restaurering kan gjennomføres presenteres i en egen rapport.publishedVersio
Marine heatwave impacts on newly-hatched planktonic larvae of an estuarine crab
Get PDFEmbargoed until 26.October 2024Climate change is imposing constant and more severe environmental challenges to coastal and marine species. Regional climate and species acclimation capacity determine the communities’ ecological response to stressors. Marine heatwave events are of serious threat to species fitness and survivorship, even more to the sensitive early- history stages of ectotherms. By combining modeled regional historical data and climate change predictions with manipulative experiments, we evaluated the potential impact of marine heatwaves in a widespread and abundant planktonic larvae of the fiddler crab Leptuca thayeri. Larvae survival was affected by temperature increase with lowest survival probability under higher temperature treatments regardless of pH conditions. Larval physiology was affected by both temperature increase and pH conditions. With heatwaves becoming more frequent, hotter, and lasting longer in the region, we could expect potential reductions in the larval recruitment and stocks with cascade ecological negative effects on estuarine habitats.acceptedVersio
Caught in the middle: bottom‑up and top‑down processes impacting recruitment in a small pelagic fsh
Get PDFUnderstanding the drivers behind fluctuations in fish populations remains a key objective in fishery science. Our predictive capacity to explain these fluctuations is still relatively low, due to the amalgam of interacting bottom-up and top-down factors, which vary across time and space among and within populations. Gaining a mechanistic understanding of these recruitment drivers requires a holistic approach, combining field, experimental and modelling efforts. Here, we use the Western Baltic Spring-Spawning (WBSS) herring (Clupea harengus) to exemplify the power of this holistic approach and the high complexity of the recruitment drivers (and their interactions). Since the early 2000s, low recruitment levels have promoted intense research on this stock. Our literature synthesis suggests that the major drivers are habitat compression of the spawning beds (due to eutrophication and coastal modification mainly) and warming, which indirectly leads to changes in spawning phenology, prey abundance and predation pressure. Other factors include increased intensity of extreme climate events and new predators in the system. Four main knowledge gaps were identified related to life-cycle migration and habitat use, population structure and demographics, life-stage specific impact of multi-stressors, and predator–prey interactions. Specific research topics within these areas are proposed, as well as the priority to support a sustainable management of the stock. Given that the Baltic Sea is severely impacted by warming, eutrophication and altered precipitation, WBSS herring could be a harbinger of potential effects of changing environmental drivers to the recruitment of small pelagic fishes in other coastal areas in the world.publishedVersio
A function-based typology for Earth’s ecosystems
Get PDFAs the United Nations develops a post-2020 global biodiversity framework for the Convention on Biological Diversity, attention is focusing on how new goals and targets for ecosystem conservation might serve its vision of ‘living in harmony with nature’1,2. Advancing dual imperatives to conserve biodiversity and sustain ecosystem services requires reliable and resilient generalizations and predictions about ecosystem responses to environmental change and management3. Ecosystems vary in their biota4, service provision5 and relative exposure to risks6, yet there is no globally consistent classification of ecosystems that reflects functional responses to change and management. This hampers progress on developing conservation targets and sustainability goals. Here we present the International Union for Conservation of Nature (IUCN) Global Ecosystem Typology, a conceptually robust, scalable, spatially explicit approach for generalizations and predictions about functions, biota, risks and management remedies across the entire biosphere. The outcome of a major cross-disciplinary collaboration, this novel framework places all of Earth’s ecosystems into a unifying theoretical context to guide the transformation of ecosystem policy and management from global to local scales. This new information infrastructure will support knowledge transfer for ecosystem-specific management and restoration, globally standardized ecosystem risk assessments, natural capital accounting and progress on the post-2020 global biodiversity framework.publishedVersio
Whose knowledge counts in nature-based solutions? Understanding epistemic justice for nature-based solutions through a multi-city comparison across Europe and Asia
Get PDFThere is increasing advocacy from academics, international agenda-setting organisations, and cities themselves for expert- and evidence driven approaches to multiple aspects of urban climate change and sustainability, including nature-based solutions. However, given growing interest in nature-based solutions research and practice towards questions of justice, it is important that the knowledge systems used to inform decisions about urban nature-based solutions are critically scrutinised. We use the lens of epistemic justice – justice in knowledge, with regard to how society defines a problem and the range of possible solutions – to assess nature-based solutions actions for climate adaptation and resilience across five cities: Amsterdam, Glasgow, Hanoi, Oslo, and Taipei. Our study finds common issues: the risk of quantifiable evidence about the distribution of NbS and its benefits closing down the aims of NbS strategies to meeting narrowly-defined indicators; the potential for self-defined communities of experts becoming de facto authorities on NbS; and the need for those tasked with implementing NbS ‘on the ground’ to have access to the fora and knowledge systems in which NbS strategies are developed. A key message is that more participation alone is insufficient to address epistemic justice concerns, unless it comes at a stage where a broad range of stakeholders (and their knowledges) can influence adaptation strategies and the role of NbS within them. Given the inter- and transdisciplinary nature of NbS scholarship, we argue attention must be focused on the potential for exclusion of key knowledge systems from policy and governance processes.publishedVersio
Marine phytoplankton community data and corresponding environmental properties from eastern Norway, 1896–2020
Get PDFTime series are essential for studying the long-term effects of human impact and climatic changes on the natural environment. Although data exist, no long-term phytoplankton dataset for the Norwegian coastal area has been compiled and made publicly available in a standardised format. Here we report on a compilation of phytoplankton data from inner Oslofjorden going back more than a century. The database contains 605 sampling events from 1896 to 2020, and environmental data has also been provided when available. Although the sampling frequency has varied over time, the high taxonomic quality and relatively similar methodology make it very useful. For the last 15 years (2006–2020), the sampling frequency has been almost monthly throughout the year. This dataset can be used for time series analysis to understand community structure and changes over time. It can also be used to study common taxa’ responses to environmental variables and changes, seasonal or annual species diversity and be useful for developing ecological indicators.publishedVersio
Shifted dynamics of plankton communities in a restored lake: exploring the effects of climate change on phenology through four decades
Get PDFLake surface temperatures have increased globally in recent decades. Climate change can affect lake biota directly via enhanced water temperatures, shorter ice cover duration and prolonged stratification, and indirectly via changes in species interactions. Changes in the seasonal dynamics of phytoplankton and zooplankton can further affect whole lake ecosystems. However, separating the effects of climate change from the more direct and dominating effects of nutrients is a challenge. Our aim was to explore the ecological effects of climate change while accounting for the effects of re-oligotrophication in Lake Mjøsa, the largest lake in Norway. While restoration measures since the 1970s have resulted in strongly reduced nutrient levels, the surface water temperature has increased by almost 0.4°C decade-1 during the same period. We analysed long-term trends and abrupt changes in environmental and biological time series as well as changes in the seasonal dynamics of individual plankton taxa. The general long-term trends in phenology were diverging for phytoplankton (later peaks) vs. zooplankton (earlier peaks). However, individual taxa of both phytoplankton and zooplankton displayed earlier peaks. Earlier peaks of the phytoplankton group Cryptophyceae can be explained by increased spring temperature or other climate-related changes. Earlier onset of population growth of certain zooplankton species (Limnocalanus macrurus and Holopedium gibberum) can also be explained by climatic change, either directly (earlier temperature increase) or more indirectly (earlier availability of Cryptophyceae as a food source). In the long run, climate-related changes in both phytoplankton and zooplankton phenology may have implications for the fish communities of this lake.publishedVersio
Environmental contaminants in freshwater food webs, 2021
Get PDFProsjektledere: Morten Jartun, Asle ØkelsrudThis report presents monitoring data from freshwater food webs and abiotic samples from Lake Mjøsa and Femunden within the Milfersk programme. Studies and monitoring of legacy and emerging contaminants have been carried out through this programme for several years, focusing on the pelagic food web. This is the first report in the monitoring program focusing on a benthic food chain (Chironomids, ruffe, roach and perch) in addition to inputs to Lake Mjøsa by analysis of lake sediments, surface waters, stormwater, effluent and sludge from a wastewater treatment plant (WWTP). The analytical programme includes the determination of a total of ̴ 260 single components.Environmental contaminants in freshwater food webs, 2021MiljødirektoratetpublishedVersio
Intercomparison 2236: pH, Conductivity, Alkalinity, NO3-N, Cl, SO3, Ca, Mg, Na, K, TOC, Tot-P, Tot-N, Al, Fe, Mn, Cd, Pb, Cu, Ni, and Zn.
Get PDFProsjektleder: Tina BryntesenTwenty-six laboratories from 15 countries accepted the invitation to join the ICP Waters chemical intercomparison and twenty-three of these successfully reported their results. Two sets of samples were prepared and distributed to the participants: one for the determination of ions and one for metals. In general, the results were of the same quality as previous years, with an overall acceptance rate of 75% (± 20% of the “true value”, and for pH and conductivity ± 0.2 pH units and ± 10%, respectively). The highest acceptance rates (≥ 90%) were obtained for aluminium, iron and chloride. The lowest acceptance rates were for total phosphorous and total nitrogen, at 33%. Total nitrogen was included for the first time this year. 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