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Response of lake metabolism to catchment inputs inferred using high-frequency lake and stream data from across the northern hemisphere
Get PDFIn lakes, the rates of gross primary production (GPP), ecosystem respiration (R), and net ecosystem production (NEP) are often controlled by resource availability. Herein, we explore how catchment vs. within lake predictors of metabolism compare using data from 16 lakes spanning 39°N to 64°N, a range of inflowing streams, and trophic status. For each lake, we combined stream loads of dissolved organic carbon (DOC), total nitrogen (TN), and total phosphorus (TP) with lake DOC, TN, and TP concentrations and high frequency in situ monitoring of dissolved oxygen. We found that stream load stoichiometry indicated lake stoichiometry for C : N and C : P (r2 = 0.74 and r2 = 0.84, respectively), but not for N : P (r2 = 0.04). As we found a strong positive correlation between TN and TP, we only used TP in our statistical models. For the catchment model, GPP and R were best predicted by DOC load, TP load, and load N : P (R2 = 0.85 and R2 = 0.82, respectively). For the lake model, GPP and R were best predicted by TP concentrations (R2 = 0.86 and R2 = 0.67, respectively). The inclusion of N : P in the catchment model, but not the lake model, suggests that both N and P regulate metabolism and that organisms may be responding more strongly to catchment inputs than lake resources. Our models predicted NEP poorly, though it is unclear why. Overall, our work stresses the importance of characterizing lake catchment loads to predict metabolic rates, a result that may be particularly important in catchments experiencing changing hydrologic regimes related to global environmental change.publishedVersio
Resipientundersøkelse for Porsgrunn og Bamble kommune i 2022 i forbindelse med utslipp av kommunalt avløpsvann
Get PDFProsjektleder: Hilde Cecilie TrannumDet er utført en resipientundersøkelse i Frierfjorden, Eidangerfjorden og Langesundsfjorden i forbindelse med utslipp av kommunalt avløpsvann. Målet var å dokumentere dagens økologiske tilstand og grad av påvirkning fra utslippene. Miljøtilstanden er klassifisert basert på kravene i vannforskriften. Undersøkelsen omfattet planteplankton, næringssalter, siktdyp og oksygen i vannmassene, samt makroalger, bløtbunnsfauna og miljøgifter, med ulike parametere i de ulike fjordene. Overvåkingen kommer i tillegg til øvrig overvåking i Grenlandsfjordene. Basert på denne overvåkingen, fikk vannforekomst Frierfjorden «moderat» økologisk tilstand, Eidangerfjorden «god» økologisk tilstand og Langesyndsfjorden «moderat» økologisk tilstand. Kjemisk tilstand var «ikke god» i Frierfjorden; den eneste av vannforekomstene som også ble undersøkt for miljøgifter.Porsgrunn og Bamble kommunepublishedVersio
Overvåking av langtransportert forurenset luft og nedbør. Årsrapport – Vannkjemiske effekter 2021
Get PDFProsjektleder: Øyvind GarmoRapporten presenterer resultater fra overvåking i 2021 av vannkjemi i forsuringsfølsomme vannforekomster. Overvåkingen omfattet; 78 tidstrendsjøer, 6 små innsjøer nær Nikel, 6 feltforskningsstasjoner og 2 elver.
The report presents the results from the 2021 monitoring of water chemistry in acid sensitive water bodies. The monitoring comprised 78 time-trend lakes, 6 small lakes close to Nikel, 6 field research stations and 2 rivers.MiljødirektoratetpublishedVersio
Overvåking av Ytre Oslofjord 2019-2023 - Årsrapport 2021
Get PDFProsjektleder: Mats WaldayJordbruk var største enkeltkilde for tilførsler av menneskeskapt fosfor og nitrogen i 2020. Avløpsrenseanlegg bidro med ca. 25%, med en svak økning i nitrogentilførseler. Glomma har klart størst tilførsel av næringsstoffer til fjorden. Syv stasjoner i fjorden får god tilstand for vann- massene, mens 11 får moderat tilstand. Hovedsakelig dårlige oksygenforhold og høye verdier av næringssalter som trekker ned tilstanden. Løst organisk stoff forklarer mer av variabiliteten i siktdypet enn klorofyll-ɑ, men med store forskjeller mellom stasjoner. Fjorden var uvanlig mørk senhøsten 2021 på grunn av mye organisk stoff. November 2021 var det en stor oppblomstring av den grønne fureflagellaten cf. Lepidodinium chlorophorum, som ga grønt vann i indre fjord. Resultatet fra strandsoneundersøkelsene fordeler stasjonene i tre grupper, hvor stasjon G10 og G21 skiller seg ut. G10 ligger nær utløpet av Numedalslågen, mens G21 ligger sørvest for utløpet til Glomma - sannsynlig at ferskvann og næringstilførsel fra disse medfører stor forekomst av blågrønn- og kiselalger og lavt artsantall. Undersøkelsene av nedre voksegrense for makroalger indikerer at stasjoner i beskyttede områder oppnår dårligere tilstand for nedre voksegrense. Bløtbunnundersøkelsene på tre stasjoner i Glommaestuaret i 2021 tyder på at fauna er negativt påvirket utover det man forventer fra de naturlige elvetilførslene.Fagrådet for Ytre OslofjordpublishedVersio
Sources of skill in lake temperature, discharge and ice-off seasonal forecasting tools
Get PDFDespite high potential benefits, the development of seasonal forecasting tools in the water sector has been slower than in other sectors. Here we assess the skill of seasonal forecasting tools for lakes and reservoirs set up at four sites in Australia and Europe. These tools consist of coupled hydrological catchment and lake models forced with seasonal meteorological forecast ensembles to provide probabilistic predictions of seasonal anomalies in water discharge, temperature and ice-off. Successful implementation requires a rigorous assessment of the tools' predictive skill and an apportionment of the predictability between legacy effects and input forcing data. To this end, models were forced with two meteorological datasets from the European Centre for Medium-Range Weather Forecasts (ECMWF), the seasonal forecasting system, SEAS5, with 3-month lead times and the ERA5 reanalysis. Historical skill was assessed by comparing both model outputs, i.e. seasonal lake hindcasts (forced with SEAS5), and pseudo-observations (forced with ERA5). The skill of the seasonal lake hindcasts was generally low although higher than the reference hindcasts, i.e. pseudo-observations, at some sites for certain combinations of season and variable. The SEAS5 meteorological predictions showed less skill than the lake hindcasts. In fact, skilful lake hindcasts identified for selected seasons and variables were not always synchronous with skilful SEAS5 meteorological hindcasts, raising questions on the source of the predictability. A set of sensitivity analyses showed that most of the forecasting skill originates from legacy effects, although during winter and spring in Norway some skill was coming from SEAS5 over the 3-month target season. When SEAS5 hindcasts were skilful, additional predictive skill originates from the interaction between legacy and SEAS5 skill. We conclude that lake forecasts forced with an ensemble of boundary conditions resampled from historical meteorology are currently likely to yield higher-quality forecasts in most cases.publishedVersio
New Approach Methodologies for the Endocrine Activity Toolbox: Environmental Assessment for Fish and Amphibians
Get PDFMultiple in vivo test guidelines focusing on the estrogen, androgen, thyroid, and steroidogenesis pathways have been developed and validated for mammals, amphibians, or fish. However, these tests are resource-intensive and often use a large number of laboratory animals. Developing alternatives for in vivo tests is consistent with the replacement, reduction, and refinement principles for animal welfare considerations, which are supported by increasing mandates to move toward an “animal-free” testing paradigm worldwide. New approach methodologies (NAMs) hold great promise to identify molecular, cellular, and tissue changes that can be used to predict effects reliably and more efficiently at the individual level (and potentially on populations) while reducing the number of animals used in (eco)toxicological testing for endocrine disruption. In a collaborative effort, experts from government, academia, and industry met in 2020 to discuss the current challenges of testing for endocrine activity assessment for fish and amphibians. Continuing this cross-sector initiative, our review focuses on the current state of the science regarding the use of NAMs to identify chemical-induced endocrine effects. The present study highlights the challenges of using NAMs for safety assessment and what work is needed to reduce their uncertainties and increase their acceptance in regulatory processes. We have reviewed the current NAMs available for endocrine activity assessment including in silico, in vitro, and eleutheroembryo models. New approach methodologies can be integrated as part of a weight-of-evidence approach for hazard or risk assessment using the adverse outcome pathway framework. The development and utilization of NAMs not only allows for replacement, reduction, and refinement of animal testing but can also provide robust and fit-for-purpose methods to identify chemicals acting via endocrine mechanisms.publishedVersio
The interplay between terrestrial organic matter and benthic macrofauna: Framework, synthesis, and perspectives
Get PDFEcosystems are shaped by physical, chemical, and biological drivers, which affect the quality and quantity of basal energy sources, with impacts that cascade to higher trophic levels. In coastal, shelf, and marine habitats, terrestrial-derived organic matter (ter-OM) can be a key driver of ecosystem structure and function. Climate change is expected to alter land–ocean connectivity in many regions, with a broad range of potential consequences for impacted ecosystems, particularly in the coastal zone. The benthic compartment is an important link between the large organic carbon pools stored on land and the marine environment. At the same time, the macrofauna plays a key role in the processing, biological uptake, and fate of ter-OM in the aquatic environment, with implications for coastal ecosystem functioning, benthic–pelagic coupling, carbon burial, and biogeochemical cycles. However, information about relationships between land–ocean connectivity (including ter-OM loads) and coastal benthic community responses remains spread across disciplines, and a broad perspective on the potential impacts of a changing climate is still missing. Here, we explore the interplay between benthic macrofaunal communities and ter-OM through a paired narrative and research weaving analysis, which combines systematic mapping and bibliometric analysis. The review describes the past development and status of the research field as well as the lack of information in some geographical regions and habitats worldwide. We highlight the role of macrofauna in carbon cycling and the growing evidence that ter-OM plays a key role in the structure and function of benthic communities, not strictly limited to estuarine habitats. Climate change poses challenges for the prediction of future ter-OM fluxes and potential macrofauna responses to this additional stressor, thus requiring new methodological approaches (e.g., multimarker approaches for OM characterization) and long-term monitoring programs across different habitats and spatiotemporal scales.publishedVersio
Kunnskapsinnhenting om forsøpling på sjøbunn i Norge
Get PDFProsjektleder: Jannike Falk-AnderssonDenne rapporten gir oversikt over kunnskapsbehov, kunnskapsstatus og kunnskapshull knyttet til forsøpling på havbunnen, med utgangspunkt i et foreslått helhetlig beslutningsrammeverk for rydding av søppel fra havbunnen. Dette omfatter grunnlag for å kunne gjøre prioritering av områder og gjenstander for rydding, vurdere negative konsekvenser av rydding relatert til valg av ryddemetode og skade på miljø, vurdere gjennomførbarhet i form av praktiske aspekter ved rydding inkludert logistikk og avfallshåndtering, samt kostnader forbundet med havbunnsrydding. Viktige kunnskapshull blir påpekt og anbefalinger blir gitt for å kunne videreutvikle et helhetlig beslutningsrammeverk som kan brukes til å veilede rydding av søppel på havbunnen. I tillegg blir norske myndigheters rolle i havbunnsrydding diskutert.MARFOpublishedVersio
Effect-Directed Analysis Based on Transthyretin Binding Activity of Per- and Polyfluoroalkyl Substances in a Contaminated Sediment Extract
Get PDFOnly a fraction of the total number of per- and polyfluoroalkyl substances (PFAS) are monitored on a routine basis using targeted chemical analyses. We report on an approach toward identifying bioactive substances in environmental samples using effect-directed analysis by combining toxicity testing, targeted chemical analyses, and suspect screening. PFAS compete with the thyroid hormone thyroxin (T4) for binding to its distributor protein transthyretin (TTR). Therefore, a TTR-binding bioassay was used to prioritize unknown features for chemical identification in a PFAS-contaminated sediment sample collected downstream of a factory producing PFAS-coated paper. First, the TTR-binding potencies of 31 analytical PFAS standards were determined. Potencies varied between PFAS depending on carbon chain length, functional group, and, for precursors to perfluoroalkyl sulfonic acids (PFSA), the size or number of atoms in the group(s) attached to the nitrogen. The most potent PFAS were the seven- and eight-carbon PFSA, perfluoroheptane sulfonic acid (PFHpS) and perfluorooctane sulfonic acid (PFOS), and the eight-carbon perfluoroalkyl carboxylic acid (PFCA), perfluorooctanoic acid (PFOA), which showed approximately four- and five-times weaker potencies, respectively, compared with the native ligand T4. For some of the other PFAS tested, TTR-binding potencies were weak or not observed at all. For the environmental sediment sample, not all of the bioactivity observed in the TTR-binding assay could be assigned to the PFAS quantified using targeted chemical analyses. Therefore, suspect screening was applied to the retention times corresponding to observed TTR binding, and five candidates were identified. Targeted analyses showed that the sediment was dominated by the di-substituted phosphate ester of N-ethyl perfluorooctane sulfonamido ethanol (SAmPAP diester), whereas it was not bioactive in the assay. SAmPAP diester has the potential for (bio)transformation into smaller PFAS, including PFOS. Therefore, when it comes to TTR binding, the hazard associated with this substance is likely through (bio)transformation into more potent transformation products.publishedVersio
Microplastics Removal from a Plastic Recycling Industrial Wastewater Using Sand Filtration
Get PDFThe removal of microplastic from wastewater collected from a plastic recycling facility was investigated, using a laboratory scale sand-filter. Wastewater samples were collected before and after the onsite sand-filter, for characterization for different polymer types, sizes, and shapes. A considerable difference in the characteristics and concentrations of microplastics was observed before and after onsite sand-filtration, demonstrating differences in the source of microplastics and/or potential contamination of the sand-filter operated at the facility. The distribution of different polymers showed polyethylene and polypropylene to be the main microplastics present in the wastewater samples. In the next stage, the samples were passed through a laboratory scale sand-filter column, to investigate the removal of microplastics. The laboratory scale sand-filter showed high efficiency (up to 100%) in removing microplastics of all polymer types, shapes, and sizes, demonstrating the effectiveness of this well-developed, and widely adopted, method for the removal of microplastics from wastewater. As the green shift and circular economy will result in more plastics being recycled, this study demonstrates the need for quantification of microplastic in effluents from plastic recycling facilities. This is important for devising appropriate microplastic removal strategies, and meeting potential discharge regulations that may come into effect in the future.publishedVersio