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ØKOSTOR 2022: Basisovervåking av store innsjøer. Utprøving av metodikk for overvåking og klassifisering av økologisk tilstand i henhold til vannforskriften
Get PDFProsjektleder: Sigrid HaandeRapporten presenterer resultatene fra det 8. året med basisovervåking av økologisk tilstand i store norske innsjøer i henhold til vannforskriften. Overvåkingen i 2022 omfattet totalt ti store innsjøer: Gjende, Krøderen, Mjøsa, Møsvatn, Selbusjøen, Altevatnet, Iešjávri, Stuorajávri og Takvatnet. Samlet økologisk tilstand på tvers av alle de undersøkte kvalitetselementene viste at Iešjávri er i svært god tiltand, mens Mjøsa, Møsvatn, Selbusjøen, Altevatn, Stuorajávri og Takvatnet er i god tilstand. Gjende er moderat tilstand og Krøderen var i dårlig tilstand og det var fisk som var utslagsgivende kvalitetselementer for den samlede klassifiseringen. Usikkerheten i tilstandsklassifiseringen anses å være middels i Mjøsa, Iešjávri, Stuorajávri og Takvatnet, middels til høy i Selbusjøen og høy i de øvrige innsjøene.MiljødirektoratetpublishedVersio
Are European Blue Economy ambitions in conflict with European environmental visions?
Get PDFWe report the outcomes of a comprehensive study of the potential consequences of the implementation of the EU Maritime Spatial Planning Directive (MSPD) in Danish waters. The analyses are anchored in a framework developed in support of data-driven Ecosystem-Based Maritime Spatial Planning. The data for the models include not only human stressors but also information on the distribution of ecosystem components ranging from planktonic communities over benthic communities to fish, seabirds and marine mammals. We have established a baseline, based on state-of-the-art data sets, with respect to combined effects upon ecosystem components. Future scenarios for the developments in human stressors were estimated for 2030 and 2050 based on information on existing policies, strategies and plans and were compared to the baseline. In addition, we developed a scenario for implementation of the Marine Strategy Framework Directive (MSFD), i.e. working towards meeting the objectives of Good Environmental Status. Our results indicate that (1) combined human stressors will possibly increase in 2030 and 2050 compared to the baseline, (2) increased combined human stressors are likely to lead to a worsening of the environmental and ecological status sensu the Marine Strategy Framework Directive and the Water Framework Directive (WFD), and (3) the MSPD implementation process appears to conflict with the MSFD and WFD objectives. Accordingly, we are sceptical of claims of an untapped potential for Blue Growth in Danish marine waters.publishedVersio
Geochemical and morphological characterization of particles originating from tunnel construction
Get PDFRock particles from drilling and blasting during tunnel construction (DB particles) are released to the aquatic environment where they may cause negative toxicological and ecological effects. However, there exists little research on the difference in morphology and structure of these particles. Despite this DB particles are assumed to be sharper and more angular than naturally eroded particles (NE particles), and in consequence cause greater mechanical abrasion to biota. Moreover, morphology of DB particles is assumed to depend on geology, thus depending on where construction takes place different morphologies may be emitted. The objectives in the current study were to investigate the morphological differences between DB and NE particles, and the influence of mineral and elemental content on DB particles. Particle geochemistry and morphology were characterized by inductively coupled plasma mass spectrometry, micro-X-ray fluorescence, X-ray diffraction, environmental scanning electron microscope interfaced with energy dispersive X-ray, stereo microscope, dynamic image analysis and coulter counter. DB particles (61–91% < 63 μm) collected from five different tunnel construction locations in Norway were 8–15% more elongated (lower aspect ratio) than NE particles from river water and sediments, although their angularity was similar (solidity; diff 0.3–0.8%). Despite distinct mineral and elemental characteristics between tunnel construction locations, DB morphology was not explained by geochemical content since only 2–2.1% of the variance was explained. This suggests that particle formation mechanisms during drilling and blasting are more influential of morphology than mineralogy, when working in granite-gneiss terrain. When tunnelling in granite-gneiss terrain, particles with greater elongation than natural particles may enter aquatic systems.publishedVersio
Claiming space: Contested coastal commons in Mumbai
Get PDFMany of the world’s cities are located on the coast, and coastal ecologies and livelihoods are under increasing pressure from rapid urban transformations and climate change. This necessitates paying attention to how coastal spaces are understood and governed, but the spatial dimensions of urban coastal commons has received comparatively little attention. How are coastal spaces framed, understood, and contested? Drawing on scholarship on socio-spatial relations, the ‘right to the city’, and spatial justice, we explore these questions through tracing the contestations around the coastal commons in Mumbai, particularly focusing on the Coastal Road project and how claims of rights and access by the Koli fishing community unfolded. The case untangles the multi-scalar framings of coastal commons as places that are intimately tied up with Koli identity, versus city planners’ view of coasts as mere ‘conduits’, with the transformation of fluid land-sea commons into legible and controllable territory. We make an argument for the notion of a ‘right to the coast as commons’ as being conducive for a more climate-resilient city that heeds the particular ecological interdependencies and stewardship of coastal communities.publishedVersio
Impacts of Riverine Floods on Morphodynamics in the Yellow River Delta
Get PDFThe geomorphological stability and ecological environment of megadeltas worldwide are of vital importance for their sustainable development. Deltaic hydro-morphodynamics is extremely sensitive to high riverine flow due to reduced sediment supply. However, the morphological evolution and response of deltas under high riverine flow have remained inadequately quantified. As one of the typical megadeltas, the Yellow River Delta (YRD), is becoming increasingly sensitive to environmental changes and intensified human interventions. In this study, a numerical model and field data were used to investigate the hydrodynamic changes and morphodynamic evolution induced by extreme river discharge in the YRD. The numerical experiments with different runoff scenarios reveal that high-energy riverine floods can cause significant hydrodynamic changes in bed shear stresses, water levels, and flow velocities, particularly in the abandoned river mouth. Moreover, it enhances the ebb-dominated tidal asymmetry, which considerably intensifies fluvial sediment resuspension and transport processes. The results also show high-energy riverine floods in the flood seasons trigger severe erosion in the Yellow River submerged delta, with a net erosion volume reaching −0.07 × 108 m3/year. The hydrodynamic increment in the abandoned river mouth is more significant, and therefore, severe erosion occurs, with the maximum erosion thickness reaching 7 m. These findings highlight the role of high riverine floods on the hydro-sediment dynamics of large river deltas under a sediment starvation condition.publishedVersio
Overvåking av vannforekomster i Ringsaker kommune i 2022
Get PDFProsjektleder: Asle ØkelsrudÅtte stasjoner i elver og bekker i Ringsaker kommune er undersøkt med fokus på eutrofieringsparametere (næringssalter) samt organisk belastning og hygieniske forhold (E. coli og intestinale enterokokker). I tillegg til de konvensjonelle måleparametere for eutrofiering, ble det gjort analyser av stabile isotoper i elvemose, og målinger av konsentrasjoner av koffein i vann for vurdering av kilder til påvirkning. Det er ikke gjort forsøk på en klassifisering av økologisk tilstand utfra resultatene, men utfra målte middelverdier er to stasjoner (i Skvaldra) og en stasjon i Trevlebekken i moderat tilstand mht. fosfor (Tot-P), mens de resterende stasjonene har middelverdier tilsvarende god tilstand. Alle stasjoner har middelverdier av nitrogen (Tot-N) tilsvarende svært god tilstand. Til tross for relativt lave konsentrasjoner av næringssalter, har alle stasjoner tidvis høye verdier av tarmbakterier, som indikerer fersk fekal forurensing. Med bakgrunn i resultater fra undersøkelsen og informasjon om arealbruk, framstår Blekabekken som mest sannsynlig påvirket av urenset avløp fra hyttefelt. Forhøyede fosforverdier på elvestasjoner uten hytter i nedbørfeltet, tyder på at fekal forurensing fra beitedyr bidrar til økt fosfortilførsel og redusert vannkvalitet. Denne undersøkelsen sannsynliggjør at kilder til redusert vannkvalitet i undersøkte vannforekomster i Ringsakerfjellet, skyldes både tilførsler fra urenset avløp fra hytter og husdyr på beite.Ringsaker kommunepublishedVersio
Puntos de inflexión en los gradientes de composición de las comunidades de plantas acuáticas de diferentes continentes
Get PDFUnravelling patterns and mechanisms of biogeographical transitions is crucial if we are to understand compositional gradients at large spatial extents, but no studies have thus far examined breakpoints in community composition of freshwater plants across continents. Using a dataset of almost 500 observations of lake plant community composition from six continents, we examined, for the first time, if such breakpoints in geographical space exist for freshwater plants and how well a suite of ecological factors (including climatic and local environmental variables) can explain transitions in community composition from the subtropics to the poles. Our combination of multivariate regression tree (MRT) analysis and k-means partitioning suggests that the most abrupt breakpoint exists between temperate to boreal regions on the one hand and freshwater plant communities harbouring mainly subtropical or Mediterranean assemblages on the other. The spatially structured variation in current climatic conditions is the most likely candidate for controlling these latitudinal patterns, although one cannot rule out joint effects of eco-evolutionary constraints in the harsher high-latitude environments and post-glacial migration lags after Pleistocene Ice Ages. Overall, our study supports the foundations of global regionalisation for freshwater plants and anticipates further biogeographical research on freshwater plant communities once datasets have been harmonised for conducting large-scale spatial analyses.publishedVersio
Miljøkonsekvensvurdering av økte utslipp av suspendert stoff til Husnesfjorden
Get PDFProsjektleder: Henrik JonssonHydro Husnes har siden Q1 2022 hatt et forhøyet utslipp av suspendert stoff (SS) til Husnesfjorden. Kjemisk analyse av utslippsvannet gir en forventning om overskridelse av bedriftens utslippsgrenser for bly, kadmium, arsen, krom og nikkel med en faktor 2-15x. Sedimentasjonsrate er beregnet fra oppsamlet materiale i sedimentfeller. Beregnede rater ligger for alle stasjoner under anvendt PNEC-verdi for akutt tildekking av sjøbunnsorganismer. Kjemisk analyse bekrefter stor spredning av utslippet, med hovedretning nordvest i utslippsrørets lengderetning. Influensområde for aluminium strekker seg minst 600 meter fra utslippspunktet. Aluminiumoksidpartiklene er i gjennomsnitt større enn de partikler som allerede finnes på sjøbunnen. Det forventes derimot ingen toksisk effekt av aluminium. Influensområde for nikkel strekker seg mer enn 800 meter fra utslippspunktet. Kobber er målt i konsentrasjoner tilsvarende tilstandsklasse 5 i oppsamlet materiale, men kobber kan ikke kobles til utslippet fra Hydro. Regresjonsanalyser viser at også kvikksølv og krom tilføres Husnesvågen fra andre utslippskilder. I konklusjon forventes ikke utslippet fra Hydro å ha påvirket resipienten negativt siden Q1 2022. Hvis utslippet vedvarer over tid vil derimot store deler av Husnesvågen dekkes av aluminiumoksidpartikler som gir endring i livsvilkår for bunnlevende organismer, og med et nikkelinnhold over EQS-verdien.Hydro Aluminium HusnespublishedVersio
Towards sustainable waste management in Myanmar – key results from the project ‘Capacity building on waste management in the Bago Region’
Get PDFProsjektleder: Ingrid NesheimThis report presents key results from the project ‘Capacity building on waste management in the Bago Region’. It synthesizes primary and secondary data on various aspects of waste management in the Bago Township, including a study of the formal and informal waste management systems and their key actors, and a study of microplastic pollution of the Bago River. Building on Action Research it further presents four pilot cases promoting sustainable waste management practices and behavioural change through a cleanup of a river side waste dump, waste management at the local market, new waste management systems and composting at selected monasteries.Royal Norwegian Embassy in MyanmarpublishedVersio
Effekter av ekstremværet «Hans» på vannkvaliteten i Mjøsa
Get PDFProsjektleder: Jan-Erik ThraneEkstremværet «Hans» rammet store deler av Sør-Norge i august 2023, og førte til storflom i Gudbrandsdalslågen og rekordhøy vannstand i Mjøsa. Denne rapporten presenterer hvordan ekstremværet påvirket vannkvaliteten i Mjøsa de etterfølgende månedene. Resultatene er basert på overvåkingsdata innsamlet gjennom den tiltaksrettede overvåkingen i vannområde Mjøsa, finansiert av Vassdragsforbundet, samt to ekstra prøvetakingstokt i september og oktober, finansiert av Miljødirektoratet.Vassdragsforbundet for Mjøsa med tilløpselverpublishedVersio