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Undersøkelse av hydrografiske og biologiske forhold i Indre Oslofjord, Årsrapport 2023
Full text linkProsjektledere: André Staalstrøm og Louise ValestrandOvervåkningen av Indre Oslofjord har i 2023 omfattet hydrografiske undersøkelser som inkluderer både plante- og dyreplankton. Kartlegging av naturtyper har også vært gjort i 2023, hvor innsamling av data i strandsonen er gjort med drone. Overvåkningsåret var sterkt preget av flom, med mye avrenning fra land. Umiddelbare effekter av dette har vært endret lysforholdet i Oslofjorden, samt økt mengde næringssalter etterfulgt av planteplanktonvekst på senhøsten.Fagrådet for vann og avløpteknisk samarbeid i indre OslofjordpublishedVersio
Evaluation of the Adriatic Sea pollution using mesozooplankton as an environmental indicator
Full text linkThe Adriatic Sea is an enclosed basin threatened by marine pollution due to its hydrographic features and anthropogenic pressure. Although zooplankton has been worldwide regarded as an immediate warning signal of contamination, limited information is available on the contamination of these organisms at the Adriatic level. Hence, this study provides comprehensive data on the presence and levels of multiple pollutants in zooplankton collected from 46 locations. With regards to legacy contaminants, both PCB and DDT levels have declined since the 1980s. Specifically, most samples were characterized by low DDT contamination (average of 3 ± 2.7 ng g− 1 dry weight) and only few of these accumulated levels of concern for what concerns PCB, pointing out possible hotspots of contamination in the central-eastern Adriatic Sea. As regards metal(loid)s, the Metal Pollution Index identified areas of concern in the north Adriatic Sea (Gulf of Venice) with high levels of Co, Cu, Hg, Cr and Pb; in the Central Adriatic Sea (Tremiti islands) with high levels of Co, Ni, Hg, Cr and Pb; in the Southern Adriatic Sea (Taranto and offshore Corfu), with high levels of most metal(loid)s, especially Cr, Ni and Zn. Certain metal(loid)s (e.g. Cd, Pb and Hg) have declined over time and most of them are lower than well-known contaminated worldwide marine ecosystems. Only Cu appears to be particularly high in the Mediterranean zooplankton. Overall, this work suggests a general improvement of the status of contamination of the Adriatic Sea.publishedVersio
Setting nutrient boundaries to protect aquatic communities: The importance of comparing observed and predicted classifications using measures derived from a confusion matrix
Full text linkDefining nutrient thresholds that protect and support the ecological integrity of aquatic ecosystems is a fundamental step in maintaining their natural biodiversity and preserving their resilience. With increasing catchment pressures and climate change, it is more important than ever to develop clear methods to establish thresholds for status classification and management of waters. This must often be achieved using complex data and should be robust to interference from additional pressures as well as ameliorating or confounding conditions. We use both artificial and real data to examine challenges in setting nutrient thresholds in unbalanced and skewed data. We found significant advantages to using binary logistic regression over other techniques. However, one of the key challenges is objectively selecting a probability from which to derive the nutrient threshold. For this purpose, the examination of the proportions of matching and mismatching status classifications of nutrients and a biological quality element using a confusion matrix is a key step that should be more widely adopted in threshold selection. We examined a large array of statistical measures of classification accuracy and their performance over combinations of skewness and imbalance in the data. The most appropriate threshold probability is a compromise between maximising overall classification accuracy and reducing mismatches expressed as commission (false positives) without excessive omission (false negatives). An application to a lake type indicated total phosphorus thresholds that would be around 50 μg l−1 lower than the threshold achieved by an ‘unguided’ approach, indicating that this approach is a very significant development meriting attention from national authorities responsible for water management.publishedVersio
Driftskontroll av kalkdoseringsanlegg i Vegårvassdraget. År 2021
Full text linkProsjektleder: Øyvind T. ØdegaardDriftskontroll av Hauglandsfoss doseringsanlegg i Storelva, Vegårvassdraget, er et verktøy for å få bedre innsyn i hvordan kalkingen fra anlegget fungerer. Denne statusrapporten gir en dokumentasjon på driften i 2021 og inneholder samtidig en fortegnelse over hendelser og avvik som kan danne grunnlag for forbedringstiltak. Ved begge pH-målestasjonene i effektområdet for kalkingen, dvs. prosessmålestasjonen ved Monane og kontrollmålestasjonen ved Nes Verk, var det flere tilfeller med for lav pH i forhold til målet. I alt ble det registrert 15 hendelser hvor pH ved Nes Verk lå under målet i 8 timer eller mer. Det lengste perioden varte i 25 døgn og hadde et avvik i forhold til målet på opptil 0,22 pH-enheter. Som tiltak for å opprettholde pH-målet ned til Nes Verk anbefales det å øke doseringen tilstrekkelig tidlig før kraftige nedbørsepisoder.Vegårshei kommunepublishedVersio
It takes two to tango: the second session of negotiations (INC-2) for a global treaty to end plastic pollution
Full text linkThe United Nations (UN) Intergovernmental Negotiating Committee (INC) has completed its second round of negotiations on a new international legally binding instrument to ‘end plastic pollution’. This paper examines the results of the second session of negotiations, which took place May 29–June 2, 2023, and analyses the trends, barriers, and themes shaping the emerging legally binding instrument. The paper considers the discussion surrounding the Options Paper as presented by the INC Secretariat and United Nations Environmental Program based upon written submissions received by UN member states prior to the second session of negotiations. These include potential elements the future treaty text may include—namely objectives, core obligations, and implementation and monitoring measures. At the second session of negotiations, progress towards consensus on these items was severely lacking. We draw on close observations via event ethnography of participants during the negotiations and document analysis. We conclude by looking towards the third round of negotiations by discussing the ongoing ‘dance’ of sorts as submissions are being asked of member states and like-minded groups to contribute to the zero draft treaty text.publishedVersio
Does Perceived Nuisance Abundance of Water Plants Match with Willingness-to-Pay for Removal? Contrasts Among Different User Categories
Full text linkDense beds of water plants can be perceived as nuisance, but this perception, however, may not be similar for different user categories, and this may affect their willingness-to-pay (WTP) for plant removal. A questionnaire survey was used to test this for residents and visitors and find underlying socio-cultural or economic drivers. We studied five cases where nuisance water plant growth is managed: the rivers Otra (Norway) and Spree (Germany), and the lakes Kemnade (Germany), Grand-Lieu (France), and Hartbeespoort Dam (South Africa). We used a different payment vehicle for residents (annual household tax) and visitors (tourist tax). The survey included questions on days spent on specific types of activity per year, the importance attached to different functions and activities, overall environmental attitude, perception of the plants, socio-demographic respondent characteristics and WTP for increased plant removal. We observed no increase in WTP for increased removal in most sites. The two most important drivers of variation in current WTP were income, and whether respondents were engaged in boating and angling and thus perceived the plants negatively. Variation in WTP among sites was considerable, and mainly related to the mixture of activities among respondents. Differences between residents and visitors were less important than those among sites. Our observations bear importance for water management: information on differences in experienced nuisance among user categories and the frequency of use by these categories is useful as guidance for the design and implementation of any plant removal plan.publishedVersio
Overvåking i referanseelver Oppsummering av data for perioden 2017-2023
Full text linkProsjektleder: Tor Erik EriksenOvervåkingsprogrammet «Overvåking i referanseelver» undersøker miljøtilstanden i norske elver og bekker med antatt liten grad av menneskelig påvirkning. Denne rapporten sammenstiller resultater og vurderer økologisk tilstand per år og per vannforekomst for perioden 2017-2023, med fokus på vannkjemiske parametere for eutrofiering og forsuring, samt de biologiske kvalitetselementene bunndyr (indeksene ASPT og RAMI), begroingsalger (indeksene PIT og AIP) og fisk (fiskeindeksen). I tillegg omfatter rapporten analyser av miljøgifter i fisk. Resultatene diskuteres med hensyn til presisjon, usikkerhet og variasjon i indeksverdier og tilstand. Resultatene viser at noen av de antatt upåvirkede vassdragene faktisk er påvirket av menneskelig aktivitet. Dette er vist gjennom analyser av fysisk-kjemiske parametere (som næringsstoffer og forsuringsparametere), kjemisk tilstand (miljøgifter) og biologiske indekser for begroingsalger, bunndyr og fisk. Datasammenstillingen viser også usikkerhet knyttet til dagens metodikk for tilstandsklassifisering og fremhever behovet for utbedringer for noen av vurderingssystemene for å øke presisjonen i vurderingene. Spesielt gjelder dette de biologiske indeksene AIP (forsuring), ASPT (eutrofiering/organisk forurensning) og fiskeindeksen, der forholdsvis mange vannforekomster ikke oppnådde den forventede tilstandsklassen svært god. Vi foreslår videre arbeid med disse indeksene for å eventuelt justere forventningsverdiene, og dermed forbedre vurderingssystemene for tilstandsklassifisering av norske vassdrag.MiljødirektoratetpublishedVersio
Trends in mercury, lead and cadmium concentrations in 27 European streams and rivers: 2000–2020
Full text linkTemporal trends for concentrations of mercury (Hg), lead (Pb) and cadmium (Cd) were evaluated from year 2000–2020 in 20 (Hg), 23 (Pb) and 11 (Cd) watercourses in remote forest catchments in Europe. Decreasing trends were observed in 15% (Hg), 39% (Pb) and 45% (Cd) of the watercourses during the period of evaluation. Decreasing trends were mainly observed between 2000 and 2005 for Hg and between 2000 and 2015 for Pb and Cd. For the last five years of the studied time period (2015–2020), more watercourses showed significant increasing, rather than decreasing Hg, Pb and Cd trends. This was interpreted as a legacy effect of metals still retained in catchment soils. The overall negative trends during the earlier part of the study period were likely driven by declining deposition of metals over Europe, especially for Pb and Cd. Other changes related to metal transport and chemistry may have contributed to the observed trends as well, including recovery from acidification and the ongoing browning of surface waters at northern latitudes. Here we found that organic carbon could explain the seasonal variation in Hg and Pb, but was not related the interannual trends. This study highlights the need for long-term monitoring and robust statistical methods that can detect multidirectional, long-term change in water chemistry.publishedVersio
Biodiversity monitoring in Europe: User and policy needs
Full text linkTo achieve the goals of the 2030 Global Biodiversity Framework, the European Biodiversity Strategy, and the EU Green Deal, biodiversity monitoring is critical. Monitoring efforts in Europe, however, suffer from gaps and biases in taxonomy, spatial coverage, and temporal resolution, resulting in fragmented and disconnected data. To assess user and policy needs in biodiversity monitoring, we employed a four-step user-centered stakeholder engagement process with over 300 stakeholders including a public stakeholder workshop, online survey, interviews, and a meeting with experts from 18 EU member states, the European Commission, and the European Environment Agency. The stakeholders identified policy needs, current challenges, and potential solutions. Based on the policy and stakeholder assessment, we recommend establishing a European Biodiversity Observation Coordinating Centre to optimize existing observation efforts, harmonize data, and enhance our ability to predict and respond to key challenges related to biodiversity loss in Europe.publishedVersio
Trends and patterns in surface water chemistry in Europe and North America between 1990 and 2020, with a focus on calcium
Full text linkProsjektleder: Rolf David VogtThe report presents trends in major anions and cations, pH, TOC and bicarbonate in surface waters in Europe and North America from 1990 to 2020. Special attention is given to trends in calcium, which showed some unexpected increases. The trends in calcium are analysed in relation to changes in bicarbonates, organic anions, and deposition loads. The surface waters show strong signs of chemical recovery.Norwegian Ministry of Climate and Environment, United Nations Economic Commission for Europe (UNECE)publishedVersio