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Søknad, overvåking og kontroll med utslipp fra landbasert akvakultur
Get PDFProsjektleder Ole-Kristian Hess-ErgaNåværende søknadsprosess legger ikke tilstrekkelig til rette for god utslippskontroll og miljøovervåking. En kombinasjon av en god veileder, oppdatert/tilpasset søknadskjema og obligatorisk forhåndskonferanse vil sikre ivaretakelse av nye aktører så vel som etablerte oppdrettere og konsulenter. I tillegg vil relevante og gode forundersøkelser, tydelige krav til dokumentasjon av driftsopplegg og anlegg, kompetanseheving hos sektormyndighetene, to-trinns søknad og klargjøring av avbøtende tiltak bidra til et bedre system. Et oppdatert prøvetakingsregime bør også innføres for å øke kunnskapsgrunnlaget. Samlet vil dette gi bedre utslippskontroll, forbedret miljøovervåking og mer nøyaktig klassifisering av miljøtilstand. Saksbehandlingen vil bli mer effektiv og forutsigbar, samt i større grad føre til likebehandling av næringsaktørene. For å heve kunnskapsgrunnlaget ytterligere forslås det å videreføre forprosjektet i et hovedprosjekt for å avdekke hvilke nye tiltak som kan føre til mer nøyaktig utslippskontroll, bedre resipientvurdering og bedre miljøovervåking for derved å tilfredsstille større landbasert produksjon og evt. nye krav.Regionalt forskingsfond VestlandpublishedVersio
Physicochemical and biological ageing processes of (micro)plastics in the environment: a multi-tiered study on polyethylene
Get PDFPollution by plastic and microplastic impacts the environment globally. Knowledge on the ageing mechanisms of plastics in natural settings is needed to understand their environmental fate and their reactivity in the ecosystems. Accordingly, the study of ageing processes is gaining focus in the context of the environmental sciences. However, laboratory-based experimental research has typically assessed individual ageing processes, limiting environmental applicability. In this study, we propose a multi-tiered approach to study the environmental ageing of polyethylene plastic fragments focusing on the combined assessment of physical and biological processes in sequence. The ageing protocol included ultraviolet irradiation in air and in a range of water solutions, followed by a biofouling test. Changes in surface characteristics were assessed by Fourier transform infrared spectroscopy, scanning electron microscopy, and water contact angle. UV radiation both in air and water caused a significant increase in the density of oxidized groups (i.e., hydroxyl and carbonyl) on the plastic surface, whereby water solution chemistry influenced the process both by modulating surface oxidation and morphology. Biofouling, too, was a strong determinant of surface alterations, regardless of the prior irradiation treatments. All biofouled samples present (i) specific infrared bands of new surface functional groups (e.g., amides and polysaccharides), (ii) a further increase in hydroxyl and carbonyl groups, (iii) the diffuse presence of algal biofilm on the plastic surface, and (iv) a significant decrease in surface hydrophobicity. This suggests that biological-driven alterations are not affected by the level of physicochemical ageing and may represent, in real settings, the main driver of alteration of both weathered and pristine plastics. This work highlights the potentially pivotal role of biofouling as the main process of plastic ageing, providing useful technical insights for future experimental works. These results also confirm that a multi-tiered laboratory approach permits a realistic simulation of plastic environmental ageing in controlled conditions.publishedVersio
Land use contribution to spatiotemporal stream water and ecological quality: Implications for water resources management in peri-urban catchments
Get PDFClimate change and intensifying agricultural production and urbanization are central factors driving the global freshwater biodiversity decline. To design sustainable green transition schemes and support urban planning, a deeper understanding of the numerous interacting physicochemical and biogeochemical processes and their relation to ecological quality becomes essential. This study thus aims to explore links between hydrological regimes and patterns evident for key water quality parameters and benthic invertebrate indicators in a peri-urban catchment that has undergone several stream restoration projects. Results indicate significant seasonal variability in discharge and physico-chemical parameters confounding the identification of sources behind detrimental impacts on ecological quality, which may lead to the implementation of inappropriate mitigation strategies. Notably, sampling at the sub-catchment level underlined the dynamic contributions of both agricultural and urban-like areas for nitrogen and phosphorus, while non-volatile carbon was mainly exported from agricultural lands. Multivariate statistical methods were used to classify benthic macro- and meioinvertebrate (specifically nematode) taxa showing poor-to-moderate and poor-to-good ecological quality, respectively. Poor ecological quality was mostly found in the upstream part of the catchment, driven by a combination of low habitat quality and periodically impaired physico-chemical conditions (e.g. dissolved oxygen, temperature, and suspended solids). In addition, the nematode-based stress index NemaSPEAR[%] (expressing the proportion of species-at-risk within a sample and specifically sensitive to the chemical contamination), indicated a TSS-related transport of contaminants to the sediment. It could also reveal both the negative impacts of different urban features (low ecological quality just downstream of combined sewer overflows), as well as the potential benefits of wastewater effluents (i.e. good ecological quality, via well-treated flow contributions and limited fine sediment accumulation especially in summer) on the stream ecosystem. Our results highlight that the use of this indicator, in combination with high frequency monitoring are promising techniques to better link the dynamic impacts of land use and spatiotemporal changes in ecological quality.publishedVersio
Ecological status assessment of clay rivers with naturally enhanced water phosphorus concentrations
Get PDFThe species composition of benthic algae changes as water phosphorus concentrations increase, and these changes can be used for ecological status assessment according to the Water Framework Directive. Natural background phosphorus concentrations in rivers and streams that are unaffected by anthropogenic impacts are usually low. Running waters draining catchments with deposits of marine clay, however, may have enhanced phosphorus concentrations, because the clay is naturally rich in apatite. Almost all clay rich areas have been cultivated for centuries, however, and fertilization has increased the soil phosphorus levels. It has, therefore, been difficult to disentangle natural from anthropogenically enhanced phosphorus in streams draining clay rich areas. We compared water phosphorus concentrations, and the Periphyton Index of Trophic Status PIT, between clay and non-clay, impacted and unimpacted rivers in Norway. We found that water phosphorus concentrations and the PIT index were higher in unimpacted clay rivers than in unimpacted non-clay rivers, indicating that natural phosphorus concentrations in clay rivers are indeed enhanced compared to rivers without deposits of marine clay. In addition, phosphate-P contributed 18–23% to total phosphorus in unimpacted clay rivers, but 33–37% in unimpacted and impacted non-clay rivers and clay rivers affected by agriculture. This indicates that the total phosphorus in unimpacted clay rivers is less bioavailable than in non-clay rivers and in impacted clay rivers. Water total phosphorus concentrations in unimpacted clay rivers significantly increased with catchment clay cover. Based on these findings, we derived new status class boundaries for the PIT index in clay rivers. Clay rivers are suggested to be assessed in only two status classes, i.e., “good or better” or “moderate or worse”, respectively. The good/moderate status class boundary for the PIT index was shown to increase with increasing catchment clay cover.publishedVersio
Evaluering av komboindeksens egnethet for tilstandsklassifisering av makroalger i sjøsonen
Get PDFProsjektleder Camilla With FagerliKomboindeksen er en ny klassifiseringsindeks for makroalger som baserer seg på vurderinger av makroalgesamfunnets tilstand i fjæresonen kombinert med vurderinger i sjøsonen. Komboindeksen har blitt utprøvd gjennom Miljødirektoratets ØKOKYST program siden 2017, og basert på erfaring fra bruk, er det ønskelig å utrede komboindeksens egnethet og vurdere om den bør inkluderes som indeks for makroalger i klassifiseringsveilederen. I rapporten foreslås justeringer av metoden som kan bidra til forbedring av indeksens presisjon for registreringene og indeksens utsagnskraft. Blant forbedringsforslagene fremheves særlig overgang fra droppkamera til undervannsdrone/ROV, samt å inkludere nedre voksegrense for sukkertare som en vurderingsparameter. Videoregistreringer i sjøsonen bidrar til å gi et mer fullstendig bilde av tilstanden til makroalgesamfunnet og kan avdekke negative forhold som ikke nødvendigvis gir utslag i fjæresonen. Komboindeksen bør derfor fortsatt inngå i ØKOKYST-overvåkingen, men basert på faglige vurderinger konkluderes det med at indeksen bør videreutvikles og et større vurderingsgrunnlag bør foreligge før komboindeksen eventuelt kan inkluderes i klassifiseringsveilederen.publishedVersio
Tiltaksorientert overvåking av Årdalsfjorden i 2021. Overvåking for Hydro Aluminium Årdal.
Get PDFProsjektleder/Hovedforfatter Sigurd ØxnevadNIVA har utført tiltaksorientert overvåking av Årdalsfjorden i 2021 på oppdrag for Hydro Aluminium Årdal. I overvåkingen er det gjort analyser av polysykliske aromatiske hydrokarboner (PAH-forbindelser) og tungmetaller (arsen, bly, kadmium, kobber, krom, kvikksølv, nikkel og sink) i prøver av blåskjell fra fem stasjoner og i sedimentprøver fra tre stasjoner. Det ble også analysert for fluorid i blåskjellprøvene. De to innerste sedimentstasjonene hadde høye konsentrasjoner av PAH-forbindelser. Sedimentene på de to stasjonene var i «svært dårlig» tilstand for PAH16. Sedimentene på den midtre stasjonen i Årdalsfjorden hadde lavere konsentrasjoner av PAH-forbindelser, og var i «moderat» tilstand for PAH16. Det var overskridelse av mange PAH-forbindelser som hører til de prioriterte stoffene. De tre sedimentstasjonene klassifiseres til «ikke god» kjemisk tilstand. Selv om det var høye konsentrasjoner av PAH-forbindelser sedimentene i Årdalsfjorden i 2021, så har det vært en god utvikling med lavere konsentrasjoner i løpet av de siste 10-20 årene. Det var høyest konsentrasjon av PAH-forbindelser i blåskjellene fra Hundshammar. Det var bare lave konsentrasjoner av PAH-forbindelser i blåskjellene fra stasjonene i den midtre og ytre delen av fjorden. Det var overskridelse av grenseverdier for de prioriterte stoffene benzo(a)pyren og fluoranten i blåskjell fra Hundshammar. Kjemisk tilstand for stasjonen Hundshammar klassifiseres derfor til «ikke god» tilstand. De andre stasjonene var i «god» kjemisk tilstand.publishedVersio
Mercury in air and soil on an urban-rural transect in East Africa
No full textThere are large knowledge gaps concerning concentrations, sources, emissions, and spatial trends of mercury (Hg) in the atmosphere in developing regions of the Southern Hemisphere, particularly in urban areas. Filling these gaps is a prerequisite for assessing the effectiveness of international regulation and for enabling a better understanding of the global transport of Hg in the environment. Here we use a passive sampling technique to study the spatial distribution of gaseous elemental Hg (Hg(0), GEM) and assess emission sources in and around Dar es Salaam, Tanzania's largest city. Included in the study were the city's main municipal waste dumpsite and an e-waste processing facility as potential sources of GEM. To complement the GEM data and for a better overview of the Hg contamination status of Dar es Salaam, soil samples were collected from the same locations where passive air samplers were deployed and analysed for total Hg. Overall, GEM concentrations ranged between <0.86 and 5.34 ng m−3, indicating significant local sources within the urban area. The municipal waste dumpsite and e-waste site had GEM concentrations elevated above the background, at 2.41 and 1.77 ng m−3, respectively. Hg concentrations in soil in the region (range 0.0067 to 0.098 mg kg−1) were low compared to those of other urban areas and were not correlated with atmospheric GEM concentrations. This study demonstrates that GEM is a significant environmental issue in the urban region of Dar es Salaam. Further studies from urban areas in the Global South are needed to better identify sources of GEM.publishedVersio
Estimating the costs and benefits of protecting a coastal amenity from climate change-related hazards: Nature based solutions via oyster reef restoration versus grey infrastructure
Get PDFThis paper examines the recreational use values associated with a coastal walking trail under threat from increased episodes of storm surges and coastal erosion, and the cost of alternative grey and nature based infrastructure options that could protect it. These options involve restoring an oyster reef bar that would act as a natural breakwater versus an impermeable revetment. The results of an on-site survey of users of the amenity and a negative binomial travel cost model demonstrate that the coastal trail has considerable recreational use value to local communities. In terms of a cost benefit analysis it was found that both protection options resulted in a positive net benefit over a 20 year time horizon but the nature based solution had a benefit cost ratio multiple times larger than the grey infrastructure alternative. The conclusions of the analysis remain valid under sensitivity analysis. The results suggest a compelling case for embedding nature based solutions in climate adaption and flood management planning for low lying coastal areas where recreational resources are under threat as it can be not only more cost effective but may also offer other ecosystem benefits to coastal communities.publishedVersio
The MicroClimate Screen – A microscale climate exposure system for assessing the effect of CO2, temperature and UV on marine microalgae
Get PDFGlobal warming and anthropogenic activities are changing the ocean, inducing profound impacts on marine life and ecosystems from changing physical and chemical factors in and above the water column. Rising surface temperatures, ocean acidification, and seasonal variations in UV radiation (UVR), modulated by water clarity and sea-ice extent, affect life cycles of the marine food-web, and directly or indirectly also the global carbon fixation. Diatoms, pelagic microalgae that are responsible for 40% of the marine productivity, have limited capability to avoid exposure to changing ocean conditions, and hence, highly relevant for model studies of the influence of climate change on growth and productivity in the marine environment. A plate-based high-throughput exposure system was constructed to assess the biological effects from relevant climate change factors on the diatom Skeletonema pseudocostatum, conducted as a chronic toxicity tests over 72 h periods. The exposure system consisted of a micro-climate unit and a light-exposure unit, enabling accurate regulation of pCO2, temperature, UVR and photosynthetic active radiation (PAR). Changes in physical factors, including pH, dissolved inorganic carbon (DIC), total alkalinity (TA), temperature and salinity in the medium, as well as reduction in growth were characterised to demonstrate performance of the micro exposure system. The results demonstrate that the exposure system successfully simulated ocean acidification and could maintain stable temperature (CV < 3%), PAR and UVR irradiance (CV < 8%). Growth inhibition responses were typically dose-dependent and verified that the micro-exposure system could be used to assess effects and adaptions to climate-relevant stressors.publishedVersio
Overvåking av begroingsalger og heterotrof begroing på 18 stasjoner i vannområde Glomma sør for Øyeren 2011 - 2021
Get PDFProsjektleder Maia Røst KileDette overvåkingsprogrammet er andre år av en 4-årig rammeavtale som NIVA har inngått med Vannområde Glomma sør for Øyeren. Målsetningen med undersøkelsen har vært å klassifisere økologisk tilstand i henhold til vannforskriften på 18 utvalgte elve- og bekkelokaliteter på bakgrunn av undersøkelser av begroingsalger og heterotrof begroing. I en totalvurdering av økologisk tilstand ble 3 lokaliteter klassifisert til å være i god tilstand i 2021, mens de resterende stasjonene var i moderat eller dårlig tilstand.publishedVersio