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Status og overordnet plan for kalksjøer i Nordland
Get PDFProsjektleder: Kirstine ThiemerHensikten med prosjektet har vært å gi en oppdatert oversikt over kalksjøer i Nordland, status på artsmangfold og tilstand, tiltaksvurdering og forslag til feltmetodikk. Pr. juli 2023 omfatter datasettet for Nordland 137 sikre kalkrike lokaliteter, hvorav 115 innsjøer og 22 dammer, med et totalt areal på 11 km2. Ifølge prediksjonsmodellen skal det være 3 104 kalkrike vannforekomster i Nordland, hvorav 1 028 innsjøer som har et samlet areal på nesten 27 km2. Kalksjøene i Nordland er artsrike med mange rødlistearter, og de fleste har god tilstand både i forhold til eutrofiering og generelt i forhold til infrastrukturindeksen, men dataene er til dels svært mangelfulle. Det er utarbeidet en oversikt over lokaliteter med behov for oppfølgende/nye undersøkelser og lokaliteter der det er behov for tiltak i forhold til eutrofiering. Vi foreslår at innsjøer i lavlandet prioriteres i den videre kartleggingen av kalkrike lokaliteter i Nordland.Statsforvalteren i NordlandpublishedVersio
Overvåking av kystvann i vannområde Hardanger 2022
Get PDFProsjektleder: Anders RuusOvervåkingen av kystvann i vannområdet Hardanger i 2022 viste følgende: Mhp. de fysisk-kjemiske kvalitetselementene viste oksygen(minimum-) konsentrasjoner moderat tilstand på stasjon Lind1 og god tilstand på stasjonene Sø7/2 og S22Sør. Siktedypet tilsvarte dårlig tilstand på samtlige av disse tre stasjonene. Vannregionspesifikke stoffer i vann (metaller; særlig sink) oversteg grenseverdiene (EQS) på alle stasjoner hvor vann ble analysert (Lind1, Sø7/2, S22Sør og S1/4). Ingen analyserte prioriterte stoffer oversteg grenseverdiene (EQS) i overflatevann. Konsentrasjoner av kvikksølv i blåskjell var derimot for høye til å klassifisere kjemisk tilstand som god på samtlige stasjoner hvor blåskjell ble analysert. Konsentrasjoner av fluorid i sjøvann var i hovedsak lavere enn kvantifiseringsgrensen på 1,5 mg/L. gjennomsnittlige konsentrasjoner av fluorid i blåskjell var lave (1,53- 2,24 mg/kg våtvekt). Det ble kun observert konsentrasjoner av thallium på ≤0,05 μg/L i overflatevann. Tl ble funnet i blåskjell i gjennomsnittskonsentrasjoner på 0,003-0,005 mg/kg våtvekt.Boliden Odda AS, Tizir Titanium & Iron AS og Fluorsid Noralf ASpublishedVersio
Tiltaksrettet vassdragsovervåking for Hurdalsvassdraget/Vorma 2022
Get PDFProsjektleder: Johnny HållRapporten presenterer resultatene fra tiltaksrettet overvåking av 18 vannlokaliteter fordelt på 12 elver og én innsjø i Vannområdet Hurdalsvassdraget /Vorma (Huvo) i 2022. Totalt 8 av 18 vannlokaliteter ble klassifisert til god eller svært god fysisk‐kjemisk tilstand med hensyn til eutrofiering i 2022. Fire vannlokaliteter ble klassifisert til moderat fysisk‐kjemisk tilstand og 6 stasjoner til dårlig tilstand. 7 vannlokaliteter hadde bedre fysisk‐kjemisk tilstand i 2022 sammenlignet med i 2021. Vannlokaliteten Nessa ble som eneste stasjon klassifisert til verre fysiskkjemisk tilstand (dårlig) sammenlignet med i 2021 (moderat). I tillegg ble Hersjøen vurdert til dårlig økologisk tilstand i 2022 basert på kvalitetselementet planteplankton, hvilket er en forverring av tilstanden sammenlignet med i 2021 (moderat). Én vannforekomst ble typifisert som leirvassdrag i 2022 (vanntype R111), mens 7 vannforekomster lå nær grensen til leirvassdrag.Vannområdet Hurdalsvassdraget/Vorma (Huvo)publishedVersio
Large-scale monitoring and risk assessment of microplastics in the Amazon River
Get PDFMicroplastics (MPs) are one of the most widespread contaminants worldwide, yet their risks for freshwater ecosystems have seldom been investigated. In this study, we performed a large monitoring campaign to assess the presence and risks of MPs in Amazonian freshwater ecosystems. We investigated MP pollution in 40 samples collected along 1500 km in the Brazilian Amazon, including the Amazon River, three major tributaries, and several streams next to the most important urban areas. MPs in the 55–5000 µm size range were characterized (size, shape, color) by microscopy and identified (polymer composition) by infrared spectroscopy. Ecotoxicological risks were assessed using chronic Species Sensitivity Distributions for effects triggered by food dilution and tissue translocation using data alignment methods that correct for polydispersity of environmental MPs and bioaccessibility. This study shows that MPs are ubiquitous contaminants in Amazonian freshwater ecosystems, with measured concentrations (55–5000 µm) ranging between 5 and 152 MPs/m3 in the Amazon River and its main tributaries, and between 23 and 74,550 MPs/m3 in urban streams. The calculated Hazardous Concentration for the 5% of species (HC5) derived from the SSDs for the entire MP range (1–5000 µm) were 1.6 × 107 MPs/m3 (95% CI: 1.2 × 106 – 4.0 × 108) for food dilution, and 1.8 × 107 MPs/m3 (95% CI: 1.5 × 106 – 4.3 × 108) for translocation. Rescaled exposure concentrations (1–5000 µm) in the Amazon River and tributaries ranged between 6.0 × 103 and 1.8 × 105 MPs/m3, and were significantly lower than the calculated HC5 values. Rescaled concentrations in urban streams ranged between 1.7 × 105 and 5.7 × 108 MPs/m3, and exceeded both calculated HC5 values in 20% of the locations. This study shows that ecological impacts by MP contamination are not likely to happen in the Amazon River and its major tributaries. However, risks for freshwater organisms may be expected in near densely populated areas, such as the cities of Manaus or Belem, which have limited wastewater treatment facilities.Large-scale monitoring and risk assessment of microplastics in the Amazon RiverpublishedVersio
Integrated Water Resources Management in Myanmar - Aquatic macrophytes in lakes in Myanmar 2014-2020 - Field survey and identification
Get PDFProsjektleder: Ingrid NesheimThis report is performed by NIVA, as part of the project Integrated Water Resources Management – Institutional Building and Training. The purpose of this report is to assist experts undertaking biological field surveys in Myanmar. The purpose of the report is to assist the Myanmar experts responsible for the aquatic macrophyte field surveys. In addition to a suggested field method for aquatic macrophyte survey in lakes in Myanmar, the report contains factsheets with short descriptions and photos of 40 hydrophyte species in Myanmar. These factsheets can be used as a supplement to other identifications keys and floras from the Asian region and serve as a “first identification step”.The Norwegian embassy in Yangon, Myanmar
Norwegian Ministry of Foreign Affairs, NorwaypublishedVersio
Kartlegging av vandringshindre i vassdrag ved bruk av folkeforskning og AMBER Barrier Tracker-appen – et pilotprosjekt
Get PDFProsjektleder: Johnny HållNIVA har på oppdrag fra Miljødirektoratet gjennomført et pilotprosjekt (2020-23) om kartlegging av vandringshindre i vassdrag ved folkeforskning og konkret ved bruk av appen ‘AMBER Barrier Tracker’. Målet med prosjektet har vært å studere hvordan folkeforskning og datainnsamling ved bruk av appen kan fungere i en forvaltningsrelevant sammenheng. Prosjektet har vært gjennomført av NIVA sammen med Miljødirektoratet og en pilotgruppe bestående av representanter fra nasjonale miljø- og interesseorganisasjoner og deres lokallag, fylkeskommuner, statsforvaltere og vannområder. Denne rapporten presenterer resultater og erfaringer fra prosjektet og gir anbefalinger til eventuelt videre arbeid. Registreringene med appen er relevante for forskere og forvaltere for å få oversikt over barrierene. God informasjon og tilrettelegging er viktige for deltakelse, og vi erfarte at det er et stykke fra å vise interesse til å faktisk gjøre en registering. Prosjektet anbefaler å opprette en nasjonal database for å sikre tilgang til innsamlede data over tid.MiljødirektoratetpublishedVersio
Three decades of change in the Skagerrak coastal ecosystem, shaped by eutrophication and coastal darkening
Get PDFGlobal coastal ecosystems are under accelerating pressure from human activities and climate change. In this study we explore a long-term time series (mostly 1990–2016) from major Norwegian rivers, together with coastal time series from the Norwegian Skagerrak coast. The aims are to: 1) analyse long-term trends in riverine loadings to Skagerrak, changes in coastal water quality and pelagic and benthic species composition, and 2) to describe the relationships between human drivers (eutrophication and coastal darkening) and community structure of benthic communities. Riverine discharge and transport increased by 23–85% over the time period, corresponding to a 40–78% increase in concentrations of suspended particulate material in coastal waters and reduced surface salinity, connected to the reported coastal darkening of coastal waters. There was a worsening in ecological status for hard-bottom benthic communities (0–30 m) and a reduction in the lower growth depth limit of several macroalgae species. A structural shift in the community composition from macroalgae towards increased abundance of animals was found to be related to coastal darkening and reduced eutrophication. The concentration of coastal inorganic nutrients (DIN, PO4) declined by 27–36%, in response to management efforts to reduce eutrophication in European regional seas. Results indicate that reduced eutrophication was related to increased ecological status of the deep soft-bottom community (350 m), with a reduction in opportunistic polychaetes and an increase in filter feeding bivalves. This work highlights how climate change and other human-induced changes in a boreal ecosystem intensifies land-ocean interactions, and calls for more adaptive monitoring, where traditional water quality programs and policies need to evolve iteratively as new information emerges and the major drivers of the systems change.publishedVersio
Combining modeling with novel field observations yields new insights into wintertime food limitation of larval fish
Get PDFRecruitment success of marine fishes is generally considered to be highly dependent on larval growth and survival. In temperate ecosystems, fish larvae are sensitive to food limitation during the low productivity seasons, particularly if water temperatures and concomitant larval metabolic costs increase due to climate change. We combined 7 years of in situ sampling of larval fish, novel observations on zooplankton via automated image analyses, and larval physiological modeling to explore feeding conditions of Atlantic herring larvae (Clupea harengus) in the North Sea. The observed plankton size-structure was close to the theoretical optimum for larval foraging, but not the biomass. Our results for autumn larvae supported Hjort's critical period hypothesis: small first-feeding larvae were predicted to have a high probability of starvation, whereas larvae > 13 mm were able to reach their maximal growth capacity. In winter, the majority of herring larvae of all tested sizes (5–27 cm) experienced food-limitation with over 35% probability of starvation. Sensitivity analysis suggested that young herring larvae improve their growth performance and probability of survival if feed not only on copepods and their life-stages but include other microplankters in their diet. Given projected warming of the North Sea, our model predicts that herring larvae would require 28% (35%) more prey biomass in autumn (winter) to sustain their growth and survival in the future. This finding together with the ongoing low recruitment of North Sea herring underscore the importance of future micro- and mesoplankton monitoring within a scope of wintertime larval fish surveys.publishedVersio
Actions Are Needed to Deal with the High Uncertainties in Tire Wear Particle Analyses
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Evaluation of the IKEU programme. An evaluation of the programme’s organization, its organs, financing and contributions
Get PDFProsjektleder: Øyvind KasteIKEU (Integrated Studies of the Effects of Liming Acidified Waters) is the national monitoring programme for long-term effects of liming in Sweden. The main focus of IKEU is to study the long-term effects of liming on lakes and streams in order to improve the knowledge base for the liming activity. The main aim of this report is to evaluate the current programme structure and IKEU’s fulfilment of the four main objectives since the last evaluation in 2009. The evaluation includes an assessment of scientific quality, the usefulness of the long-term monitoring series produced by the programme, whether the programme produces relevant knowledge for decision making, and to what extent decisionmakers implement the knowledge produced by the programme.The Swedish Agency for Marine and Water ManagementpublishedVersio