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  • 1.
    Ahlinder, Jon
    et al.
    Division of CBRN Defence and Security, FOI, Swedish Defence Research Agency, Umeå, Sweden.
    Mathisen, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Sjödin, Andreas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen. Division of CBRN Defence and Security, FOI, Swedish Defence Research Agency, Umeå, Sweden.
    Nilsson, Elin
    Division of CBRN Defence and Security, FOI, Swedish Defence Research Agency, Umeå, Sweden.
    Forsman, Mats
    Division of CBRN Defence and Security, FOI, Swedish Defence Research Agency, Umeå, Sweden.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Thelaus, Johanna
    Division of CBRN Defence and Security, FOI, Swedish Defence Research Agency, Umeå, Sweden.
    Oligotyping reveals divergent responses of predation resistant bacteria to aquatic productivity and plankton compositionManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    Predation-resistance has been suggested to be a key for persistence of pathogenic bacteria in aquatic environments. Little is known about driving factors for different types of protozoa resistant bacteria (PRB). We studied if presence of PRB is linked to specific plankton taxa, the aquatic nutrient state, or predation pressure on bacteria. Nineteen freshwater systems were sampled and analyzed for PRB, plankton composition and physicochemical variables. Three PRB genera were identified; Pseudomonas, Mycobacterium and Rickettsia. Use of minimum entropy decomposition algorithm and phylogenetic analysis showed that different nodes (representing OTUs of high taxonomic resolution) matched to environmental isolates of the three genera. Links between the PRB genera and specific plankton taxa were found, but showed different relationships depending on if 18S rRNA OTU or microscopy data were used in the analysis. Mycobacterium spp. was negatively correlated to aquatic nutrient state, while Pseudomonas showed the opposite pattern. Rickettsia spp. was positively related to predation pressure on bacteria. Both Mycobacterium and Rickettsia were more abundant in systems with high eukaryotic diversity, while Pseudomonas occurred abundantly in waters with low prokaryotic diversity. The different drivers may be explained by varying ecological strategies, where Mycobacterium and Rickettsia are slow growing and have an intracellular life style, while Pseudomonas is fast growing and opportunistic. Here we give an insight to the possibilities of newly advanced methods such as sequencing and oligotyping to link potential pathogens with biomarkers. This as a tool to assist predictions of the occurrence and persistence of environmental pathogens.

  • 2.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Ett ekosystem i ständig förändring2014Inngår i: Havsutsikt Tema Hav och Klimat, nr 2, s. 9-11Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 3.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Ahlinder, J.
    Mathisen, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Hagglund, M.
    Backman, S.
    Nilsson, E.
    Sjodin, A.
    Thelaus, J.
    Predators and nutrient availability favor protozoa-resisting bacteria in aquatic systems2018Inngår i: Scientific Reports, E-ISSN 2045-2322, Vol. 8, artikkel-id 8415Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The long co-existence of bacteria and protozoa has led to the development of bacterial protozoa resistance strategies, which are suggested to serve as drivers for the evolution of pathogenic bacteria. However, the ecological mechanisms underpinning selection for protozoa-resistance in aquatic bacteria are poorly known. To assess the role of nutrient availability and predation-pressure on selection for protozoa-resisting bacteria (PRB), an enrichment-dilution experiment was designed using laboratory microcosms containing natural lake water. PRB was monitored by screening 16S rRNA amplicon sequence data for reads assigned to bacteria that previously has been shown to resist degradation by amoebae. To estimate the effects of the microbial food web dynamics (microscopy of; heterotrophic bacteria, phytoplankton, protozoa and rotifers) and physicochemical variables on the PRB abundance in the study system, a joint species distribution modelling approach was used. The predation-pressure (ratio between predator and bacterial biomass) had a positive effect on the abundance of the PRB genus Mycobacterium, while perturbation (enrichment and dilution) favored the PRB genus Pseudomonas that dominated the bacterial community in the disturbed systems. Our results show that PRB with different ecological strategies can be expected in water of high and intermediate nutrient levels and after major disturbances of an aquatic system.

    Fulltekst (pdf)
    fulltext
  • 4.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Ahlinder, Jon
    Division of CBRN Defence and Security, Swedish Defence Research Agency, FOI, SE-901 82 Umeå, Sweden.
    Mathisen, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Bäckman, Stina
    Division of CBRN Defence and Security, Swedish Defence Research Agency, FOI, SE-901 82 Umeå, Sweden.
    Nilsson, Elin
    Division of CBRN Defence and Security, Swedish Defence Research Agency, FOI, SE-901 82 Umeå, Sweden.
    Hammarström, Moa
    Division of CBRN Defence and Security, Swedish Defence Research Agency, FOI, SE-901 82 Umeå, Sweden.
    Sjödin, Andreas
    Division of CBRN Defence and Security, Swedish Defence Research Agency, FOI, SE-901 82 Umeå, Sweden.
    Thelaus, Johanna
    Division of CBRN Defence and Security, Swedish Defence Research Agency, FOI, SE-901 82 Umeå, Sweden.
    Aquatic ecosystems at risk for occurrence of pathogenic bacteriaManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    Pathogenic bacteria occur naturally in aquatic systems. Co-existence of bacteria and protozoa has led to development of predation resistance strategies, which is suggested to serve as a driver for evolution of pathogenic bacteria. However, the ecological mechanisms for selection for different types of predation resistant and pathogenic bacteria are poorly known. To disentangle effects from nutrient availability and protozoan predation pressure on the occurrence of varying predation resistant bacterial genera, an enrichment-dilution experiment was performed where an aquatic bacterial community was exposed to protozoa. Operational taxonomical units, specific for three predation resistant bacterial genera were identified; Pseudomonas, Rickettsia and Mycobacterium. These genera are also known to harbor species that are potentially pathogenic to mammals. Rickettsia and Mycobacterium were promoted where protozoa were abundant and the predation pressure high, while Pseudomonas dominated the bacterial community at the highest nutrient level where the predation pressure on bacteria were low. Our study thus indicates that waters of all nutrient states can harbor pathogenic bacteria, but that bacteria with different ecological strategies occur depending on nutrient level and perturbation. The generative model approach presented here provide a possibility to integrate environmental data in prediction models of pathogens in complex environments.

  • 5.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Brugel, Sonia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Paczkowska, Joanna
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Rowe, Owen F.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Department of Food and Environmental Sciences, Division of Microbiology and Biotechnology, University of Helsinki, Helsinki, Finland.
    Figueroa, Daniela
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Kratzer, S.
    Legrand, C.
    Influence of allochthonous dissolved organic matter on pelagic basal production in a northerly estuary2018Inngår i: Estuarine, Coastal and Shelf Science, ISSN 0272-7714, E-ISSN 1096-0015, Vol. 204, s. 225-235Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Phytoplankton and heterotrophic bacteria are key groups at the base of aquatic food webs. In estuaries receiving riverine water with a high content of coloured allochthonous dissolved organic matter (ADOM), phytoplankton primary production may be reduced, while bacterial production is favoured. We tested this hypothesis by performing a field study in a northerly estuary receiving nutrient-poor, ADOM-rich riverine water, and analyzing results using multivariate statistics. Throughout the productive season, and especially during the spring river flush, the production and growth rate of heterotrophic bacteria were stimulated by the riverine inflow of dissolved organic carbon (DOC). In contrast, primary production and photosynthetic efficiency (i.e. phytoplankton growth rate) were negatively affected by DOC. Primary production related positively to phosphorus, which is the limiting nutrient in the area. In the upper estuary where DOC concentrations were the highest, the heterotrophic bacterial production constituted almost 100% of the basal production (sum of primary and bacterial production) during spring, while during summer the primary and bacterial production were approximately equal. Our study shows that riverine DOC had a strong negative influence on coastal phytoplankton production, likely due to light attenuation. On the other hand DOC showed a positive influence on bacterial production since it represents a supplementary food source. Thus, in boreal regions where climate change will cause increased river inflow to coastal waters, the balance between phytoplankton and bacterial production is likely to be changed, favouring bacteria. The pelagic food web structure and overall productivity will in turn be altered.

    Fulltekst (pdf)
    fulltext
  • 6.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Grinienė, Evelina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Marine Research Institute, Klaipėda University, Klaipėda, Lithuania.
    Berglund, Åsa M. M.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Brugel, Sonia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Gorokhova, Elena
    Department of Environmental Science, Stockholm University, Stockholm, Sweden.
    Figueroa, Daniela
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Gallampois, Christine
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Ripszam, Matyas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Microbial food web changes induced by terrestrial organic matter and elevated temperature in the coastal northern Baltic Sea2023Inngår i: Frontiers in Marine Science, E-ISSN 2296-7745, Vol. 10, artikkel-id 1170054Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Climate change has been projected to cause increased temperature and amplified inflows of terrestrial organic matter to coastal areas in northern Europe. Consequently, changes at the base of the food web favoring heterotrophic bacteria over phytoplankton are expected, affecting the food web structure. We tested this hypothesis using an outdoor shallow mesocosm system in the northern Baltic Sea in early summer, where the effects of increased temperature (+ 3°C) and terrestrial matter inputs were studied following the system dynamics and conducting grazing experiments. Juvenile perch constituted the highest trophic level in the system, which exerted strong predation on the zooplankton community. Perch subsequently released the microbial food web from heavy grazing by mesozooplankton. Addition of terrestrial matter had a stronger effect on the microbial food web than the temperature increase, because terrestrial organic matter and accompanying nutrients promoted both heterotrophic bacterial production and phytoplankton primary production. Moreover, due to the shallow water column in the experiment, terrestrial matter addition did not reduce the light below the photosynthesis saturation level, and in these conditions, the net-autotrophy was strengthened by terrestrial matter enrichment. In combination with elevated temperature, the terrestrial matter addition effects were intensified, further shifting the size distribution of the microbial food web base from picoplankton to microphytoplankton. These changes up the food web led to increase in the biomass and proportion of large-sized ciliates (>60 µm) and rotifers. Despite the shifts in the microbial food web size structure, grazing experiments suggested that the pathway from picoplankton to nano- and microzooplankton constituted the major energy flow in all treatments. The study implies that the microbial food web compartments in shallow coastal waters will adjust to climate induced increased inputs of terrestrial matter and elevated temperature, and that the major energy path will flow from picoplankton to large-sized ciliates during the summer period.

    Fulltekst (pdf)
    fulltext
  • 7.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Hansen, W
    Wänstrand, I
    Huseby, S
    Wikner, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Strategi för kontrollerande övervakning av kustvatten i Bottenhavets vattendistrikt2008Rapport (Fagfellevurdert)
  • 8.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Hansen, Wenche
    Länsstyrelsen Västernorrland.
    Wänstrand, Ingrid
    Länsstyrelsen Gävleborg.
    Huseby, Siv
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Wikner, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Strategi för kontrollerande övervakning av Bottenhavets vattendistrikt2008Rapport (Annet vitenskapelig)
    Abstract [sv]

    Ett pelagialprogram har tagits fram för övervakning i relativt opåverkade referensområden i kustvattentyperna 16 t.o.m.19 i Bottemhavet. Programmet bör kunna ligga till grund för uppföljning av internationella, nationella och regionala miljömål samt följa upp ekologisk status. Den rumsliga variationen samt mellanårsvariationen hos pelagiala variabler i Bottenhavsområdet har använts som utgångspunkt för att beräkna provtagningsbehovet. Det föreslagna programmet innebär att mellan 48 och 60 provtagningar årsperiod, varefter ekologisk status kan bedömas. Designen gör det möjligt att med 80 % säkerhet bedöma ekologisk status med mätdata som ligger minst 20 % från klassgränserna. Mätprogrammet är designat för provtagningar -årsperiod. Stationer har slumpats ut i de olika typerna, och förslag på årliga provtagningslokaler anges i rapporten. Eftersom djupet vid de olika stationerna varierar, bör de flesta pelagiala variablerna provtas vid ett diskret djup i övre delen av vattenmassan, t.ex. 1 m djup. Av vetenskapliga och ekonomiska skäl är det viktigt att pelagialprogrammet samordnas för hela Bottenhavet.

    För mjukbottenfauna bedöms det befintliga integrerade programmet för trendanalys i Bottenhavet kunna tillgodose Vattendirektivets behov för kontrollerande övervakning i distriktet. Detta under förutsättning att Sundsvallsbuktens program fortsätter och att de nya nationella och regionala provtagningsområdena i södra Bottenhavet (Gräsö) etableras och drivs. Dimensioneringen av nuvarande nationellt och regionalt bottenfaunaprogram och områdesövervakning men har även visat sig vara väl anpassat för bedömningar inom ramen för Vattendirektivet. Enligt bedömningsgrunden bör minst 5 stationer användas för klassning av ekologisk status. Dessa stationer måste dock inte ligga inom samma vattenförekomst, utan kan vara lokaliserade i angränsande vattenförekomster. Den ekologiska statusen för mjukbottenfauna i enskilda vattenförekomster klassas genom extrapolering med hjälp av data från närbelägna områden med liknande bottenmiljö och påverkansgrad.

    Befintlig fiskebeståndsövervakning föreslås fortlöpa för att möjliggöra uppföljning av förändringar. En utökning av antalet övervakningsområden föreslås dock för att upprätta minst ett referensområde per inre och yttre kustvattentyp. En kombination av stratifierad och slumpmässig övervakning av fiskebestånden enligt nuvarande strategi föreslås, där djupintervallen stratifieras medan stationerna slumpas ut i respektive djupintervall.

    Provfiske och provtagning för miljögiftsanalys av fisk bör samordnas till samma provtagningstillfälle. Vidare bör den modell för samfinansiering och samordning som idag tillämpas av kustlänen i Bottniska viken för övervakning av fiskbestånd, samt och miljögiftsövervakning av fisk, fortlöpa även framöver.

    De ämnen som ingår i det pågående nationella programmet för miljögifter i fisk bör mätas även i de nya föreslagna områdena. När EU:s dotterdirektiv för prioriterade ämnen är beslutat och Vattenmyndigheterna fastställt miljökvalitetsnormer för särskilda förorenande ämnen, bör en översyn göras och ytterligare ämnen som är aktuella för Bottenhavet införlivas i övervakningsprogrammet. Miljögiftsövervakning i fisk bedöms kunna mätas med ett maximalt avstånd på 75 km mellan stationsområdena. Bedömning och extrapolera mätvärdena.

    För samtliga delprogram har en grova uppskattningar av kostnader för genomförandet gjorts.

    Fulltekst (pdf)
    Samordnat Mätprogram Bottenhavet
  • 9.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Höglander, Helena
    Karlsson, Chatarina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Huseby, Siv
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Key role of phosphorus and nitrogen in regulating cyanobacterial community composition in the northern Baltic Sea2015Inngår i: Estuarine, Coastal and Shelf Science, ISSN 0272-7714, E-ISSN 1096-0015, Vol. 164, s. 161-171Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Despite cyanobacteria being a key phytoplankton group in the Baltic Sea, the factors governing their community structure are still poorly understood. Here, we studied the occurrence of the orders Chroococcales, Oscillatoriales and Nostocales, and potentially explanatory variables at five locations in the northern Baltic Sea from June–September, 1998–2012. Cyanobacteria constituted 1–36% of the total phytoplankton biomass along the north–south gradient. In the Bothnian Bay, Chroococcales and Oscillatoriales dominated the cyanobacterial community, whereas in the Bothnian Sea and northern Baltic Proper, Nostocales was the dominant group. The dominance of Chroococcales was coupled to low salinity and low total phosphorus, whereas Oscillatoriales correlated with high total nitrogen and low salinity. Nostocales correlated to high total phosphorus, inorganic phosphorus and salinity. Chroococcales showed an increase over time in the offshore Bothnian Bay, whereas Nostocales increased in the coastal Bothnian Sea and coastal Baltic Proper. The increase of Nostocales in the coastal Bothnian Sea was explained by a rise in total phosphorus and decrease in dissolved inorganic nitrogen compared to an increase of total nitrogen and phosphorus in the coastal Baltic Proper. No significant trends were observed in the cyanobacterial community in the offshore Bothnian Sea and the offshore northern Baltic Proper. We concluded that Chroococcales may be a useful indicator for increased phosphorus levels in waters with low phosphorus concentrations, whereas Nostocales could be used as a quality indicator for increasing phosphorus concentrations in waters with low inorganic N/P ratios (<20), such as in the coastal Bothnian Sea and Baltic Proper.

  • 10.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Joanna, Paczkowska
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Brugel, Sonia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Rowe, Owen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Figueroa, Daniela
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Kratzer, Susanne
    Stockholm University Institutionen för ekologi miljö och botanik 106 91 Stockholm.
    Marked impact of allochthonous dissolved organic matter on estuarine primary and bacterial productionManuskript (preprint) (Annet vitenskapelig)
  • 11.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Jurgensone, Iveta
    Rowe, Owen F.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Simonelli, Paolo
    Bignert, Anders
    Lundberg, Erik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Karlsson, Jan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Can Humic Water Discharge Counteract Eutrophication in Coastal Waters?2013Inngår i: PLOS ONE, E-ISSN 1932-6203, Vol. 8, nr 4, s. e61293-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A common and established view is that increased inputs of nutrients to the sea, for example via river flooding, will cause eutrophication and phytoplankton blooms in coastal areas. We here show that this concept may be questioned in certain scenarios. Climate change has been predicted to cause increased inflow of freshwater to coastal areas in northern Europe. River waters in these areas are often brown from the presence of high concentrations of allochthonous dissolved organic carbon ( humic carbon), in addition to nitrogen and phosphorus. In this study we investigated whether increased inputs of humic carbon can change the structure and production of the pelagic food web in the recipient seawater. In a mesocosm experiment unfiltered seawater from the northern Baltic Sea was fertilized with inorganic nutrients and humic carbon (CNP), and only with inorganic nutrients (NP). The system responded differently to the humic carbon addition. In NP treatments bacterial, phytoplankton and zooplankton production increased and the systems turned net autotrophic, whereas the CNP-treatment only bacterial and zooplankton production increased driving the system to net heterotrophy. The size-structure of the food web showed large variations in the different treatments. In the enriched NP treatments the phytoplankton community was dominated by filamentous >20 mu m algae, while in the CNP treatments the phytoplankton was dominated by picocyanobacteria <5 mu m. Our results suggest that climate change scenarios, resulting in increased humic-rich river inflow, may counteract eutrophication in coastal waters, leading to a promotion of the microbial food web and other heterotrophic organisms, driving the recipient coastal waters to net-heterotrophy.

    Fulltekst (pdf)
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  • 12.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Karlsson, Chatarina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Hajdu, Susanna
    Stockholms universitet.
    Höglander, Helena
    Stockholms universitet.
    Skjevik, Ann-Turi
    SMHI.
    Pelagial biologi / växtplankton2010Inngår i: Havet: om miljötillståndet i svenska havsområden. 2010 / [ed] Kristina Viklund (huvudredaktör) Ulrika Brenner, Annika Tidlund, Marie Svärd, Stockholm: Naturvårdsverket, 2010, s. 32-33Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 13.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Karlsson, Chatarina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Huseby, Siv
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Höglander, Helena
    Mer fosfor ger mer cyanobakterier i norra Östersjön2013Inngår i: Havet, s. 51-54Artikkel, forskningsoversikt (Annet vitenskapelig)
    Abstract [sv]

    I flera områden i norra Östersjön har cyanobakterierna ökat under de senaste tio till femton åren. I Bottenhavets och Egentliga Östersjöns kustområden ökar de kvävefixerande cyanobakterierna. I Bottenvikens utsjö är det den småcelliga och kolonibildande gruppen Chroococcales som blir fler. Förändringarna beror i flera fall på ökande halter av fosfor.

  • 14.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Meier, H.E. Markus
    Ripszam, Matyas
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Yrkes- och miljömedicin.
    Rowe, Owen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Wikner, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Haglund, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Eilola, Kari
    Legrand, Catherine
    Figueroa, Daniela
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Paczkowska, Joanna
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Lindehoff, Elin
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Elmgren, Ragnar
    Projected future climate change and Baltic Sea ecosystem management2015Inngår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 44, nr Suppl 3, s. S345-S356Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Climate change is likely to have large effectson the Baltic Sea ecosystem. Simulations indicate 2–4 Cwarming and 50–80 % decrease in ice cover by 2100.Precipitation may increase *30 % in the north, causingincreased land runoff of allochthonous organic matter(AOM) and organic pollutants and decreased salinity.Coupled physical–biogeochemical models indicate that, inthe south, bottom-water anoxia may spread, reducing codrecruitment and increasing sediment phosphorus release,thus promoting cyanobacterial blooms. In the north,heterotrophic bacteria will be favored by AOM, whilephytoplankton production may be reduced. Extra trophiclevels in the food web may increase energy losses andconsequently reduce fish production. Future managementof the Baltic Sea must consider the effects of climatechange on the ecosystem dynamics and functions, as wellas the effects of anthropogenic nutrient and pollutant load.Monitoring should have a holistic approach, encompassingboth autotrophic (phytoplankton) and heterotrophic (e.g.,bacterial) processes.

    Fulltekst (pdf)
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  • 15.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Meier, Markus
    SMHI och Stockholms universitet.
    Hur påverkas Östersjön?2010Inngår i: Sverige i nytt klimat: våtvarm utmaning / [ed] Birgitta Johansson, Stockholm: Forskningsrådet Formas, 2010, s. 117-132Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 16.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Samuelsson, K
    Haecky, P
    Albertsson, J
    Changes in the pelagic microbial food web due to artificial eutrophication2006Inngår i: Aquat Ecol, Vol. 40, s. 299-313Artikkel i tidsskrift (Fagfellevurdert)
  • 17.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Selstam, Eva
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Hagström, Åke
    Vertical transport of lipid in seawater1993Inngår i: Marine Ecology Progress Series, ISSN 0171-8630, E-ISSN 1616-1599, Vol. 98, nr 1-2, s. 149-155Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Lipids in seawater act as solvents and transporters of lipophilic organic pollutants. To investigate a possible transport route of lipophilic pollutants, the vertical flux of lipid was quantified during an annual cycle in the northern Baltic Sea. The lipid content in both sedimenting material and different size fractions of seawater was analyzed. During the year, 8 g lipid m-2 sedimented out from the photic zone to the benthic system. The sedimentation of lipid accounted for 300 to 400 % of the average standing stock of pelagic lipid and was concentrated in the spring bloom period (April-June) when 70 % of the total lipid sedimentation occurred. About 30 % of the produced pelagic lipid settled out from the system. In seawater the lipid maximum occurred at the end of the spring bloom, shortly after nutrient depletion, indicating a stress response in the algae. Since lipid sedimentation is concentrated in the spring bloom, removal of lipophilic organic pollutants may be important during this period.

  • 18.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Tamminen, Timo
    Lehtinen, Sirpa
    Jürgens, Klaus
    Labrenz, Matthias
    Viitasalo, Markku
    The pelagic food web2017Inngår i: Biological oceanography of the Baltic sea / [ed] Pauline Snoeijs, Hendrik Schubert, Teresa Radziejewska, Dordrecht: Springer Netherlands, 2017, s. 281-332Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]
    1. Environmental drivers and food web structure in the pelagic zone vary from south to north in the Baltic Sea. 
    2. While nitrogen is generally the limiting nutrient for primary production in the Baltic Sea, phosphorus is the limiting nutrient in the Bothnian Bay. 
    3. In the Gulf of Bothnia the food web is to a large extent driven by terrestrial allochthonous material, while autochthonous production dominates in the other parts of the Baltic Sea. 
    4. Changes in bacterioplankton, protist and zooplankton community composition from south to north are mainly driven by salinity. 
    5. Bacteria are crucial constituents of the pelagic food web (microbial loop) and in oxygen-poor and anoxic bottom waters where they mediate element transformations. 
    6. Diatoms and dinoflagellates are the major primary producers in the pelagic zone. Summer blooms of diazotrophic (nitrogen-fixing) filamentous cyanobacteria are typical of the Baltic Sea, especially in the Baltic Sea proper and the Gulf of Finland. 
    7. The mesozooplankton (mainly copepods and cladocerans) channel energy from primary producers and the microbial food web to fish and finally to the top predators in the pelagic system (waterbirds and mammals). 
    8. Herring and sprat populations are affected by the foraging intensity of their main predator (cod), and therefore the environmental conditions that affect cod may also influence mesozooplankton due to food web effects "cascading down the food web". 
    9. Anthropogenic pressures, such as overexploitation of fish stocks, eutrophication, climate change, introduction of non-indigenous species and contamination of top predators by hazardous substances, cause changes in the pelagic food web that may have consequences for the balance and stability of the whole ecosystem.
  • 19.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Wikner, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Klimatförändringar kan leda till mindre fisk i havet2016Inngår i: Havet: om miljötillståndet i svenska havsområden. 2015/2016, Göteborg: Havs- och vattenmyndigheten , 2016, s. 25-28Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 20.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Wikner, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Pelagisk biologi2004Inngår i: Bottniska viken: årsrapport från den marina miljöövervakningen. 2003, Skydd av havsområden gagnar fisken, Hörnefors: Umeå marina forskningscentrum (UMF) , 2004, s. 11-13Kapittel i bok, del av antologi (Fagfellevurdert)
  • 21.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Zhao, Li
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Brugel, Sonia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Figueroa, Daniela
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Huseby, Siv
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Metabarcoding vs Microscopy - comparison of methods to monitor phytoplankton communities2023Inngår i: ACS - ES & T Water, E-ISSN 2690-0637, Vol. 3, nr 8, s. 2671-2680Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    Phytoplankton are used worldwide to monitor environmental status in aquatic systems. Long-time series of microscopy-analyzed phytoplankton are available from many monitoring stations. The microscopy-method is however time consuming and has short-comings. DNA metabarcoding has been suggested as an alternative method, but the consistency between different methods need further investigation. We performed a comparative study of microscopy and metabarcoding analyzing micro- and nanophytoplankton. For metabarcoding, 25-1000 ml seawater were filtered, DNA extracted and the 18S and 16S rRNA gene amplicons sequenced. For microscopy, based on the Utermöhl method we evaluated the use of three metrics: abundance, biovolume and carbon biomass. At the genus, species, and unidentified taxa level, metabarcoding generally showed higher taxonomic diversity than microscopy, and diversity was already captured at the lowest filtration volume tested, 25 ml. Metabarcoding and microscopy displayed relatively similar distribution pattern at the group level. The results showed that the relative abundances of the 18S rRNA amplicon at the group level best fitted the microscopy carbon biomass metric. The results are promising for implementing DNA metabarcoding as a complement to microscopy in phytoplankton monitoring, especially if databases would be improved and group level indexes could be applied to classify the environmental state of water bodies.

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  • 22. Andersson-Nordström, Agneta
    Flagellates in the marine microbial food web: the ecology of a mixotrophic nanoflagellate, Ochromonas sp.1989Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Nanoflagellates were found to be abundant in a coastal area of the northern Bothnian Sea. The maximum concentration of nanoflagellates, approximately 8000 cells ml-1, was observed in July, coinciding with a decrease in the abundance of cyanobacteria. Pigmented and non-pigmented nanoflagellates were approximately equally distributed throughout the year. Most of the identified genera are known as being phagotrophic, independent if autotrophic or not.

    A non-cyst-forming pigmented flagellate, Ochromonas sp., was isolated and nutritionally characterized. This chrysophycean flagellate was shown to be a mainly heterotrophic organism: Photosynthesis was too poor to support multiplication of the cells, whereas when feeding on bacteria, high growth rates were obtained. The biological function of the photosynthetic apparatus is suggested to be a survival mechanism during poor bacterial conditions.

    The flagellate grazed bacteria selectively, preferring cyanobacteria and large cells of heterotrophic bacteria, presumably depending on size-selective grazing. Despite higher growth rates of the bacteria in the sea during summer (July) than spring (May), heterotrophic bacteria in the sea was observed to be smaller in the summer. Nanoflagellates showed a maximum in July, and by selective grazing of large bacteria they might have caused the decrease in the average size of the bacteria and the decrease in the abundance of cyanobacteria.

    During the consumption of bacteria the flagellate was shown to remineralize nutrients at high rates and excrete dissolved free amino acids. Assuming the existence of a protozoan predator-prey chain of several trophic levels, it seems likely that a significant part of the nutrients fixed by primary producers is remineralized in the euphotic zone. Furthermore, data from this work indicate that flagellate activity may be a significant source of dissolved free amino acids, utilizable for the heterotrophic bacteria.

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  • 23.
    Ask, Jenny
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Rowe, Owen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Brugel, Sonia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Strömgren, Mårten
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Byström, Pär
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Importance of coastal primary production in the northern Baltic Sea2016Inngår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 45, nr 6, s. 635-648Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, we measured depth-dependent benthic microalgal primary production in a Bothnian Bay estuary to estimate the benthic contribution to total primary production. In addition, we compiled data on benthic microalgal primary production in the entire Baltic Sea. In the estuary, the benthic habitat contributed 17 % to the total annual primary production, and when upscaling our data to the entire Bothnian Bay, the corresponding value was 31 %. This estimated benthic share (31 %) is three times higher compared to past estimates of 10 %. The main reason for this discrepancy is the lack of data regarding benthic primary production in the northern Baltic Sea, but also that past studies overestimated the importance of pelagic primary production by not correcting for system-specific bathymetric variation. Our study thus highlights the importance of benthic communities for the northern Baltic Sea ecosystem in general and for future management strategies and ecosystem studies in particular.

  • 24.
    Bandara, Tharindu
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Department of Animal Science, Faculty of Animal Science and Export Agriculture, Uva Wellassa University, Badulla, Sri Lanka.
    Brugel, Sonia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Lau, Danny Chun Pong
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Retention of essential fatty acids in fish differs by species, habitat use and nutritional quality of prey2023Inngår i: Ecology and Evolution, E-ISSN 2045-7758, Vol. 13, nr 6, artikkel-id e10158Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Abstract Algae-produced long-chain polyunsaturated fatty acids (LC-PUFA; with ≥20 carbon atoms) are key biomolecules for consumer production and animal health. They are transferred to higher trophic levels and accumulated in food chains. However, LC-PUFA accumulation in consumers and their trophic transfer vary with the diet quality and the physiological demand for LC-PUFA of consumers. The goal of this study was to investigate spatial and taxonomic differences in LC-PUFA retention of coastal fish predators that potentially differ in their habitat use (benthic versus pelagic) and prey quality. We analyzed the fatty acid (FA) composition of common fish species, namely roach and European perch, as well as their potential prey from benthic and pelagic habitats in three bays of the northern Baltic Sea. We then assessed whether the fish LC-PUFA retention differed between species and among the study bays with different diet quality, that is, LC-PUFA availability. Our data indicated taxon-specific differences in the retention of LC-PUFA and their precursor FA in fish (i.e., short-chain PUFA with <20 carbon atoms). Perch did not show any spatial variation in the retention of all these FA, while roach showed spatial differences in the retention of docosahexaenoic acid (DHA) and their precursor FA, but not eicosapentaenoic acid (EPA). Data suggest that diet quality and trophic reliance on benthic prey underlay the DHA retention differences in roach. Although the PUFA supply might differ among sites, the low spatial variation in LC-PUFA content of perch and roach indicates that both fishes were able to selectively retain dietary LC-PUFA. Climate change together with other existing human-caused environmental stressors are expected to alter the algal assemblages and lower their LC-PUFA supply for aquatic food webs. Our findings imply that these stressors will pose heterogeneous impacts on different fish predators. We advocate further investigations on how environmental changes would affect the nutritional quality of the basal trophic level, and their subsequent impacts on LC-PUFA retention, trophic ecology, and performance of individual fish species.

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  • 25.
    Bartels, Pia
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Ask, Jenny
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Karlsson, Jan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Climate Impacts Research Centre (CIRC), Department of Ecology and Environmental Science, Umeå University, Abisko, Sweden.
    Giesler, Reiner
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Climate Impacts Research Centre (CIRC), Department of Ecology and Environmental Science, Umeå University, Abisko, Sweden.
    Allochthonous Organic Matter Supports Benthic but Not Pelagic Food Webs in Shallow Coastal Ecosystems2018Inngår i: Ecosystems (New York. Print), ISSN 1432-9840, E-ISSN 1435-0629, Vol. 21, nr 7, s. 1459-1470Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Rivers transport large amounts of allochthonous organic matter (OM) to the ocean every year, but there are still fundamental gaps in how allochthonous OM is processed in the marine environment. Here, we estimated the relative contribution of allochthonous OM (allochthony) to the biomass of benthic and pelagic consumers in a shallow coastal ecosystem in the northern Baltic Sea. We used deuterium as a tracer of allochthony and assessed both temporal variation (monthly from May to August) and spatial variation (within and outside river plume). We found variability in allochthony in space and time and across species, with overall higher values for zoobenthos (26.2 +/- 20.9%) than for zooplankton (0.8 +/- 0.3%). Zooplankton allochthony was highest in May and very low during the other months, likely as a result of high inputs of allochthonous OM during the spring flood that fueled the pelagic food chain for a short period. In contrast, zoobenthos allochthony was only lower in June and remained high during the other months. Allochthony of zoobenthos was generally higher close to the river mouth than outside of the river plume, whereas it did not vary spatially for zooplankton. Last, zoobenthos allochthony was higher in deeper than in shallower areas, indicating that allochthonous OM might be more important when autochthonous resources are limited. Our results suggest that climate change predictions of increasing inputs of allochthonous OM to coastal ecosystems may affect basal energy sources supporting coastal food webs.

    Fulltekst (pdf)
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  • 26.
    Berglund, Johnny
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Jürgens, Klaus
    Bruchmüller, Iris
    Wedin, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Use of group-specific PCR primers for identification of chrysophytes by denaturing gradient gel electrophoresis2005Inngår i: Aquatic Microbial Ecology, ISSN 0948-3055, E-ISSN 1616-1564, ISSN 0948-3055, Vol. 39, nr 2, s. 171-182Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The chrysophytes Chrysophyceae and Synurophyceae are ecologically important groups of autotrophic, mixotrophic and heterotrophic flagellates. The smallest forms are difficult to identify by classical microscopy but have important functions both as primary producers and as consumers of bacteria in the aquatic food chain. Group-specific primers for amplification of the 18S small sub-unit rRNA gene were developed for analysis of chrysophyte diversity by denaturing gradient gel electrophoresis (DGGE). Two different primer pairs were tested. The first primer pair (EukC1-F–Chryso-R) primarily targeted Paraphysomonadaceae and Ochromonadales, which generally have heterotrophic or mixotrophic nutrition. The second primer pair (EukC2-F–Chryso-R) targeted both Chrysophyceae and Synurophyceae. The primer pairs were tested for PCR amplification of the 18S rRNA gene of 25 cultured chrysophyte species and 6 other closely related nanoplanktonic species. Both primer pairs performed well, since PCR products were obtained for the corresponding chrysophyte cultures. None of the non-chrysophyte species were amplified with these primers. PCR products of chrysophyte cultures could be separated by DGGE in a denaturing gradient from 40 to 60%. In order to test this PCR-DGGE system for natural planktonic systems, we used field samples from a brackish water area (Baltic Sea) and a freshwater lake. The most intense DGGE bands were excised, sequenced and compared to sequences in GenBank. All obtained sequences grouped within the chrysophytes. Thus, the method seems to be promising for examining chrysophyte diversity in planktonic systems.

  • 27.
    Berglund, Johnny
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Müren, Umut
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Båmstedt, Ulf
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Efficiency of a phytoplankton-based and a bacterial-based food web in a pelagic marine system2007Inngår i: Limnology and Oceanography, Vol. 52, nr 1, s. 121-131Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    he food web efficiency in two contrasting food webs, one phytoplankton based and one bacteria based, was studied in a mesocosm experiment using seawater from the northern Baltic Sea. Organisms included in the experiment were bacteria, phytoplankton, protozoa, and mesozooplankton (copepods). A phytoplankton-based food web was generated by incubating at a high light level with the addition of nitrogen and phosphorus (NP). A bacteria-based food web was created by adding carbon, nitrogen, and phosphorus (CNP) and incubating at a lower light level. In the CNP treatment bacteria dominated the productivity (91%), while in the NP treatment phytoplankton were dominant producers (74%). The phytoplankton community in the NP treatment was dominated by autotrophic nanoflagellates. The food web efficiency, defined as mesozooplankton productivity per basal productivity (phytoplankton + bacteria), was 22% in the phytoplankton-based food web and 2% in the bacteria-based food web. This discrepancy could be explained by 1�xtra trophic levels in the bacteria-based food web where carbon passed through flagellates and ciliates before reaching mesozooplankton, while in the phytoplankton-based food web there was a direct pathway from phytoplankton to mesozooplankton. The results were supported by stable isotope analysis of mesozooplankton. We propose that climate change, with increased precipitation and river runoff in the Baltic Sea, might favor a bacteria-based food web and thereby reduce pelagic productivity at higher trophic levels.

  • 28.
    Berglund, Johnny
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Samuelsson, Kristina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Kull, Tomas
    Muren, Umut
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Relative strength of resource and predation limitation of heterotrophic nanoflagellates in a low-productive sea area2005Inngår i: Journal of Plankton Research, ISSN 0142-7873, E-ISSN 1464-3774, Vol. 27, nr 9, s. 923-935Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The magnitude of resource and predation limitation of heterotrophic nanoflagellates (HNF) was studied in two short-term enclosure experiments performed in a low-productive sea area in the northern Baltic Sea in 2001. A cross-factorial design was used to simultaneously assess the relative importance of the two factors. Resource limitation was removed by adding bacteria, and predation limitation was eliminated by selective filtration. The first experiment was performed in June just after the spring bloom decline and the second in September at the end of the productive season. Resource limitation prevailed during both experiments, contributing to 60% of the net growth increase in June and 74% in September. Removal of predators had a significant effect only in June. Evidence for simultaneous resource and predation limitation was thus found only during the post-bloom situation. The results were applied to a model on resource and predation control of HNF abundances. To evaluate seasonal differences, field data on HNF and bacteria from a whole year study were applied to the model. Except for a few occasions during spring, the model indicated prevailing resource control of HNF at two locations with slightly different productivity.

  • 29.
    Berglund, Åsa M. M.
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Gallampois, Christine
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Ripszam, Matyas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen. Department of Chemistry and Industrial Chemistry, University of Pisa, Pisa, Italy.
    Larsson, Henrik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Figueroa, Daniela
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Griniene, Evelina
    Marine Research Institute, Klaipėda University, Klaipėda, Lithuania.
    Byström, Pär
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Gorokhova, Elena
    Department of Environmental Science, Stockholm University, Stockholm, Sweden.
    Haglund, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Effects on the food-web structure and bioaccumulation patterns of organic contaminants in a climate-altered Bothnian Sea mesocosms2023Inngår i: Frontiers in Marine Science, E-ISSN 2296-7745, Vol. 10, artikkel-id 1244434Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Climate change is expected to alter global temperature and precipitation patterns resulting in complex environmental impacts. The proposed higher precipitation in northern Scandinavia would increase runoff from land, hence increase the inflow of terrestrial dissolved organic matter (tDOM) in coastal regions. This could promote heterotrophic bacterial production and shift the food web structure, by favoring the microbial food web. The altered climate is also expected to affect transport and availability of organic micropollutants (MPs), with downstream effects on exposure and accumulation in biota. This study aimed to assess climate-induced changes in a Bothnian Sea food web structure as well as bioaccumulation patterns of MPs. We performed a mesocosms-study, focusing on aquatic food webs with fish as top predator. Alongside increased temperature, mesocosm treatments included tDOM and MP addition. The tDOM addition affected nutrient availability and boosted both phytoplankton and heterotrophic bacteria in our fairly shallow mesocosms. The increased tDOM further benefitted flagellates, ciliates and mesozooplankton, while the temperature increase and MP addition had minor effect on those organism groups. Temperature, on the other hand, had a negative impact on fish growth and survival, whereas tDOM and MP addition only had minor impact on fish. Moreover, there were indications that bioaccumulation of MPs in fish either increased with tDOM addition or decreased at higher temperatures. If there was an impact on bioaccumulation, moderately lipophilic MPs (log Kow 3.6 - 4.6) were generally affected by tDOM addition and more lipophilic MPs (log Kow 3.8 to 6.4) were generally affected by increased temperature. This study suggest that both increased temperatures and addition of tDOM likely will affect bioaccumulation patterns of MPs in shallow coastal regions, albeit with counteracting effects.

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  • 30. Bertos-Fortis, Mireia
    et al.
    Farnelid, Hanna M.
    Lindh, Markus V.
    Casini, Michele
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Pinhassi, Jarone
    Legrand, Catherine
    Unscrambling Cyanobacteria Community Dynamics Related to Environmental Factors2016Inngår i: Frontiers in Microbiology, E-ISSN 1664-302X, Vol. 7, artikkel-id 625Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Future climate scenarios in the Baltic Sea project an increase of cyanobacterial bloom frequency and duration, attributed to eutrophication and climate change. Some cyanobacteria can be toxic and their impact on ecosystem services is relevant for a sustainable sea. Yet, there is limited understanding of the mechanisms regulating cyanobacterial diversity and biogeography. Here we unravel successional patterns and changes in cyanobacterial community structure using a 2-year monthly time series during the productive season in a 100 km coastal-offshore transect using microscopy and high-throughput sequencing of 16S rRNA gene fragments. A total of 565 cyanobacterial OTUs were found, of which 231 where filamentous/colonial and 334 picocyanobacterial. Spatial differences in community structure between coastal and offshore waters were minor. An "epidemic population structure" (dominance of a single cluster) was found for Aphanizomenon/Dolichospermum within the filamentous/colonial cyanobacterial community. In summer, this cluster simultaneously occurred with opportunistic clusters/OTUs, e.g., Nodulana spumigena and Pseudanabaena. Picocyanobacteria, Synechococcus/Cyanobium, formed a consistent but highly diverse group. Overall, the potential drivers structuring summer cyanobacterial communities were temperature and salinity. However, the different responses to environmental factors among and within genera suggest high niche specificity for individual OTUs. The recruitment and occurrence of potentially toxic filamentous/colonial clusters was likely related to disturbance such as mixing events and short-term shifts in salinity, and not solely dependent on increasing temperature and nitrogen-limiting conditions. Nutrients did not explain further the changes in cyanobacterial community composition. Novel occurrence patterns were identified as a strong seasonal succession revealing a tight coupling between the emergence of opportunistic picocyanobacteria and the bloom of filamentous/colonial clusters. These findings highlight that if environmental conditions can partially explain the presence of opportunistic picocyanobacteria, microbial and trophic interactions with filamentous/colonial cyanobacteria should also be considered as potential shaping factors for single-celled communities. Regional climate change scenarios in the Baltic Sea predict environmental shifts leading to higher temperature and lower salinity; conditions identified here as favorable for opportunistic filamentous/colonial cyanobacteria. Altogether, the diversity and complexity of cyanobacterial communities reported here is far greater than previously known, emphasizing the importance of microbial interactions between filamentous and picocyanobacteria in the context of environmental disturbances.

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  • 31.
    Bidleman, Terry
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Agosta, Kathleen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Brorström-Lundén, Eva
    Haglund, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Hansson, Katarina
    Laudon, Hjalmar
    Newton, Seth
    Nygren, Olle
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Ripszam, Matyas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Wiberg, Karin
    Atmospheric pathways of chlorinated pesticides and natural bromoanisoles in the northern Baltic Sea and its catchment2015Inngår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. Suppl 3, nr 44, s. 472-483Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Long-range atmospheric transport is a major pathway for delivering persistent organic pollutants to the oceans. Atmospheric deposition and volatilization of chlorinated pesticides and algae-produced bromoanisoles (BAs) were estimated for Bothnian Bay, northern Baltic Sea, based on air and water concentrations measured in 2011-2012. Pesticide fluxes were estimated using monthly air and water temperatures and assuming 4 months ice cover when no exchange occurs. Fluxes were predicted to increase by about 50 % under a 2069-2099 prediction scenario of higher temperatures and no ice. Total atmospheric loadings to Bothnian Bay and its catchment were derived from air-sea gas exchange and "bulk'' (precipitation ? dry particle) deposition, resulting in net gains of 53 and 46 kg year(-1) for endosulfans and hexachlorocyclohexanes, respectively, and net loss of 10 kg year(-1) for chlordanes. Volatilization of BAs releases bromine to the atmosphere and may limit their residence time in Bothnian Bay. This initial study provides baseline information for future investigations of climate change on biogeochemical cycles in the northern Baltic Sea and its catchment.

    Fulltekst (pdf)
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  • 32.
    Bidleman, Terry
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Agosta, Kathleen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Brugel, Sonia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Ericson, Lars
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Hansson, Katarina
    Swedish Environmental Research Institute (IVL), Gothenburg, Sweden.
    Nygren, Olle
    Umeå universitet, Medicinska fakulteten.
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Sources and pathways of halomethoxybenzenes in northern Baltic estuaries2023Inngår i: Frontiers in Marine Science, E-ISSN 2296-7745, Vol. 10, artikkel-id 1161065Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Introduction: Thousands of halogenated natural products (HNPs) are generated in the ocean and on land. A subset of these, halomethoxybenzenes (HMBs), are released from both natural and anthropogenic sources. Here we consider: 1. Brominated anisoles (BAs), transformation products of bromophenols. 2. Drosophilin A methyl ether (DAME: 1,2,4,5-tetrachloro-3,6-dimethoxybenzene), a secondary metabolite of terrestrial fungi. 3. Tetrachloroveratrole (TeCV: 1,2,3,4-tetrachloro-5,6-dimethoxybenzene), a lignin byproduct found in bleached kraft mill effluent. 4. Pentachloroanisole (PeCA), a metabolite of the wood preservative pentachlorophenol.

    Methods: We examined several ecosystem compartments to determine sources and exchange processes for these HMBs: air, precipitation, rivers, forest fungi and litter, and water from northern Baltic estuaries and offshore. Samples were analyzed for HMBs by capillary gas chromatography – quadrupole mass spectrometry.

    Results and discussion: All four types of HMBs were found in air, and BAs, DAME and TeCV were also present in precipitation. BAs and DAME were common in rivers and estuaries, whereas TeCV was low and PeCA was below detection. DAME was identified in several species of fungi and in forest litter; TeCV was occasionally present, but BAs and PeCA were below detection. Concentrations of BAs were higher in estuaries than in rivers or offshore waters, showing that estuaries are hot spots for production. BAs were negatively or not correlated with chlorophyll-a, suggesting contribution by heterotrophic bacteria as well as known production by phytoplankton and macroalgae. DAME was negatively or not correlated with BAs and did not appear to be produced in the estuaries; fungi and forest litter containing fungal mycelia are suggested as sources. HMBs volatilize from sea and land, disperse through the atmosphere, and return via precipitation and rivers. Production and biogeochemical cycles are influenced by climate change and we suggest BAs and DAME for following partitioning and exchange processes.

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  • 33.
    Bidleman, Terry
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Brorström-Lundén, Eva
    IVL, Swedish Environmental Research Institute (IVL), Gothenburg, Sweden.
    Brugel, Sonia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Ericson, Lars
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Hansson, Katarina
    IVL, Swedish Environmental Research Institute (IVL), Gothenburg, Sweden.
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Halomethoxybenzenes in air of the Nordic region2023Inngår i: Environmental Science and Ecotechnology, ISSN 2666-4984, Vol. 13, artikkel-id 100209Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Halomethoxybenzenes (HMBs) are a group of compounds with natural and anthropogenic origins. Here we extend a 2002–2015 survey of bromoanisoles (BAs) in the air and precipitation at Råö on the Swedish west coast and Pallas in Subarctic Finland. New BAs data are reported for 2018 and 2019 and chlorinated HMBs are included for these and some previous years: drosophilin A methyl ether (DAME: 1,2,4,5-tetrachloro-3,6-dimethoxybenzene), tetrachloroveratrole (TeCV: 1,2,3,4-tetrachloro-5,6-dimethoxybenzene), and pentachloroanisole (PeCA). The order of abundance of HMBs at Råö was ΣBAs > DAME > TeCV > PeCA, whereas at Pallas the order of abundance was DAME > ΣBAs > TeCA > PeCA. The lower abundance of BAs at Pallas reflects its inland location, away from direct marine influence. Clausius-Clapeyron (CC) plots of log partial pressure (Pair)/Pa versus 1/T suggested distant transport at both sites for PeCA and local exchange for DAME and TeCV. BAs were dominated by distant transport at Pallas and by both local and distant sources at Råö. Relationships between air and precipitation concentrations were examined by scavenging ratios, SR = (ng m−3)precip/(ng m−3)air. SRs were higher at Pallas than Råö due to greater Henry's law partitioning of gaseous compounds into precipitation at colder temperatures. DAME is produced by terrestrial fungi. We screened 19 fungal species from Swedish forests and found seven of them contained 0.01–3.8 mg DAME per kg fresh weight. We suggest that the volatilization of DAME from fungi and forest litter containing fungal mycelia may contribute to atmospheric levels at both sites.

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  • 34.
    Bidleman, Terry
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Jantunen, Liisa M.
    Kucklick, John R.
    Kylin, Henrik
    Letcher, Robert J.
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Wong, Fiona
    A review of halogenated natural products in Arctic, Subarctic and Nordic ecosystems2019Inngår i: Emerging Contaminants, ISSN 2405-6650, E-ISSN 2405-6642, Vol. 5, s. 89-115Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Halogenated natural products (HNPs) are organic compounds containing bromine, chlorine, iodine, and rarely fluorine. HNPs comprise many classes of compounds, ranging in complexity from halocarbons to higher molecular weight compounds, which often contain oxygen and/or nitrogen atoms in addition to halogens. Many HNPs are biosynthesized by marine bacteria, macroalgae, phytoplankton, tunicates, corals, worms, sponges and other invertebrates. This paper reviews HNPs in Arctic, Subarctic and Nordic ecosystems and is based on sections of Chapter 2.16 in the Arctic Monitoring and Assessment Program (AMAP) assessment Chemicals of Emerging Arctic Concern (AMAP, 2017) which deal with the higher molecular weight HNPs. Material is updated and expanded to include more Nordic examples. Much of the chapter is devoted to “bromophenolic” HNPs, viz bromophenols (BPs) and transformation products bromoanisoles (BAs), hydroxylated and methoxylated bromodiphenyl ethers (OH-BDEs, MeO-BDEs) and polybrominated dibenzo-p-dioxins (PBDDs), since these HNPs are most frequently reported. Others discussed are 2,2′ -dimethoxy-3,3′ ,5,5′ -tetrabromobiphenyl (2,2′ -dimethoxy-BB80), polyhalogenated 1′- methyl-1,2′-bipyrroles (PMBPs), polyhalogenated 1,1′ -dimethyl-2,2′ -bipyrroles (PDBPs), polyhalogenated N-methylpyrroles (PMPs), polyhalogenated N-methylindoles (PMIs), bromoheptyl- and bromooctyl pyrroles, (1R,2S,4R,5R,1′E)-2-bromo-1-bromomethyl-1,4-dichloro-5-(2′-chloroethenyl)-5- methylcyclohexane (mixed halogenated compound MHC-1), polybrominated hexahydroxanthene derivatives (PBHDs) and polyhalogenated carbazoles (PHCs). Aspects of HNPs covered are physicochemical properties, sources and production, transformation processes, concentrations and trends in the physical environment and biota (marine and freshwater). Toxic properties of some HNPs and a discussion of how climate change might affect HNPs production and distribution are also included. The review concludes with a summary of research needs to better understand the role of HNPs as “chemicals of emerging Arctic concern”.

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  • 35.
    Bidleman, Terry F.
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Agosta, Kathleen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Haglund, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Liljelind, Per
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Hegmans, Alyse
    Jantunen, Liisa M.
    Nygren, Olle
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Poole, Justen
    Ripszam, Matyas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Sea-air exchange of bromoanisoles and methoxylated bromodiphenylethers in the Northern Baltic2016Inngår i: Marine Pollution Bulletin, ISSN 0025-326X, E-ISSN 1879-3363, Vol. 112, nr 1-2, s. 58-64Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Halogenated natural products in biota of the Baltic Sea include bromoanisoles (BAs) and methoxylated bromodiphenyl ethers (MeO-BDEs). We identified biogenic 6-MeO-BDE47 and 2'-MeO-BDE68 in Baltic water and air for the first time using gas chromatography - high resolution mass spectrometry. Partial pressures in air were related to temperature by: log p/Pa=m/T(K)+b. We determined Henry's law constants (HLCs) of 2,4-dibromoanisole (2,4-DiBA) and 2,4,6-tribromoanisole (2,4,6-TriBA) from 5 to 30°C and revised our assessment of gas exchange in the northern Baltic. The new water/air fugacity ratios (FRs) were lower, but still indicated net volatilization in May-June for 2,4-DiBA and May - September for 2,4,6-TriBA. The net flux (negative) of BAs from Bothnian Bay (38,000km2) between May - September was revised from -1319 to -532kg. FRs of MeO-BDEs were >1, suggesting volatilization, although this is tentative due to uncertainties in their HLCs and binding to dissolved organic carbon.

  • 36.
    Bidleman, Terry F.
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Agosta, Kathleen
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Haglund, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Nygren, Olle
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Ripszam, Matyas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Air-water exchange of brominated anisoles in the northern baltic sea2014Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 48, nr 11, s. 6124-6132Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Bromophenols produced by marine algae undergo O-methylation to form bromoanisoles (BAs), which are exchanged between water and air. BAs were determined in surface water of the northern Baltic Sea (Gulf of Bothnia, consisting of Bothnian Bay and Bothnian Sea) during 2011-2013 and on a transect of the entire Baltic in September 2013. The abundance decreased in the following order: 2,4,6-tribromoanisole (2,4,6-TBA) > 2,4-dibromoanisole (2,4-DBA) ≫ 2,6-dibromoanisole (2,6-DBA). Concentrations of 2,4-DBA and 2,4,6-TBA in September were higher in the southern than in the northern Baltic and correlated well with the higher salinity in the south. This suggests south-to-north advection and dilution with fresh riverine water enroute, and/or lower production in the north. The abundance in air over the northern Baltic also decreased in the following order: 2,4,6-TBA > 2,4-DBA. However, 2,6-DBA was estimated as a lower limit due to breakthrough from polyurethane foam traps used for sampling. Water/air fugacity ratios ranged from 3.4 to 7.6 for 2,4-DBA and from 18 to 94 for 2,4,6-TBA, indicating net volatilization. Flux estimates using the two-film model suggested that volatilization removes 980-1360 kg of total BAs from Bothnian Bay (38000 km(2)) between May and September. The release of bromine from outgassing of BAs could be up to 4-6% of bromine fluxes from previously reported volatilization of bromomethanes and bromochloromethanes.

  • 37.
    Bidleman, Terry F.
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Brugel, Sonia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Ericson, Lars
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Haglund, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Kupryianchyk, Darya
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Lau, Danny C. P.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Liljelind, Per
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Lundin, Lisa
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Tysklind, Anders
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Bromoanisoles and Methoxylated Bromodiphenyl Ethers in Macroalgae from Nordic Coastal Regions2019Inngår i: Environmental Science: Processes & Impacts, ISSN 2050-7887, E-ISSN 2050-7895, s. 881-892Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Marine macroalgae are used worldwide for human consumption, animal feed, cosmetics and agriculture. In addition to beneficial nutrients, macroalgae contain halogenated natural products (HNPs), some of which have toxic properties similar to those of well-known anthropogenic contaminants. Sixteen species of red, green and brown macroalgae were collected in 2017–2018 from coastal waters of the northern Baltic Sea, Sweden Atlantic and Norway Atlantic, and analyzed for bromoanisoles (BAs) and methoxylated bromodiphenyl ethers (MeO-BDEs). Target compounds were quantified by gas chromatography-low resolution mass spectrometry (GC-LRMS), with qualitative confirmation in selected species by GC-high resolution mass spectrometry (GC-HRMS). Quantified compounds were 2,4-diBA, 2,4,6-triBA, 2′-MeO-BDE68, 6-MeO-BDE47, and two tribromo-MeO-BDEs and one tetrabromo-MeO-BDE with unknown bromine substituent positions. Semiquantitative results for pentabromo-MeO-BDEs were also obtained for a few species by GC-HRMS. Three extraction methods were compared; soaking in methanol, soaking in methanol–dichloromethane, and blending with mixed solvents. Extraction yields of BAs did not differ significantly (p > 0.05) with the three methods and the two soaking methods gave equivalent yields of MeO-BDEs. Extraction efficiencies of MeO-BDEs were significantly lower using the blend method (p < 0.05). For reasons of simplicity and efficiency, the soaking methods are preferred. Concentrations varied by orders of magnitude among species: ∑2BAs 57 to 57 700 and ∑5MeO-BDEs < 10 to 476 pg g−1 wet weight (ww). Macroalgae standing out with ∑2BAs >1000 pg g−1 ww were Ascophyllum nodosumCeramium tenuicorneCeramium virgatumFucus radicansFucus serratusFucus vesiculosusSaccharina latissimaLaminaria digitata, and Acrosiphonia/Spongomorpha sp. Species A. nodosumC. tenuicorneChara virgataF. radicans and F. vesiculosus (Sweden Atlantic only) had ∑5MeO-BDEs >100 pg g−1ww. Profiles of individual compounds showed distinct differences among species and locations.

    Fulltekst (pdf)
    fulltext
  • 38.
    Bidleman, Terry F.
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå Marine Sciences Centre.
    Haglund, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Will Climate Change Influence Production and Environmental Pathways of Halogenated Natural Products?2020Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 54, nr 11, s. 6468-6485Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Thousands of halogenated natural products (HNPs) pervade the terrestrial and marine environment. HNPs are generated by biotic and abiotic processes and range in complexity from low molecular mass natural halocarbons (nHCs, mostly halomethanes and haloethanes) to compounds of higher molecular mass which often contain oxygen and/or nitrogen atoms in addition to halogens (hHNPs). nHCs have a key role in regulating tropospheric and stratospheric ozone, while some hHNPs bioaccumulate and have toxic properties similar those of anthropogenic-persistent organic pollutants (POPs). Both chemical classes have common sources: biosynthesis by marine bacteria, phytoplankton, macroalgae, and some invertebrate animals, and both may be similarly impacted by alteration of production and transport pathways in a changing climate. The nHCs scientific community is advanced in investigating sources, atmospheric and oceanic transport, and forecasting climate change impacts through modeling. By contrast, these activities are nascent or nonexistent for hHNPs. The goals of this paper are to (1) review production, sources, distribution, and transport pathways of nHCs and hHNPs through water and air, pointing out areas of commonality, (2) by analogy to nHCs, argue that climate change may alter these factors for hHNPs, and (3) suggest steps to improve linkage between nHCs and hHNPs science to better understand and predict climate change impacts.

  • 39.
    Blackburn, Nicholas
    et al.
    MicroWISE, Ebeltoft, Denmark.
    Haecky, Pia
    MicroWISE, Ebeltoft, Denmark.
    Jurgensone, Iveta
    Latvian Institute of Aquatic Ecology, Riga, Latvia.
    Griniene, Evelina
    Marine Research Institute, Klaipėda University, Klaipėda, Lithuania.
    Brugel, Sonia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Carstensen, Jacob
    Department of Ecoscience, Aarhus University, Roskilde, Denmark.
    The use of an automated organism tracking microscope in mesocosm experiments2022Inngår i: Limnology and Oceanography: Methods, E-ISSN 1541-5856, Vol. 20, nr 12, s. 768-780Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A method for automatically counting and measuring sizes and motility behavior of zooplankton and phytoplankton in water samples is presented. Two video cameras are focused on separate optical chambers of different sizes. The chambers are filled and emptied repeatedly by synchronized pumps. Real-time motion analysis is performed by computer on the respective video feeds. Fluorescence from chlorophyll a (Chl a) is imaged at single pixel resolution. Measured parameters for individual organisms include size, swimming velocity, motility patterns, and chlorophyll fluorescence density. The system was tested during a mesocosm experiment where it was mounted on one of several mesocosm columns. The results were validated against Chl a measurements and microscopy counts. A sampling interval of 1 per day revealed detailed dynamics of chlorophyll activity as well as shifts in both the phytoplankton and zooplankton community structure over the course of a month. A helix coefficient, a metric related to organism motility behavior, showed substantial variation over time, consistent with changing plankton communities. Sampling rates as frequent as 1 per hour enables detailed analysis of diurnal vertical migration and similar phenomena at fixed sampling points.

    Fulltekst (pdf)
    fulltext
  • 40. Blenckner, Thorsten
    et al.
    Österblom, Henrik
    Larsson, Per
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Elmgren, Ragnar
    Baltic Sea ecosystem-based management under climate change: Synthesis and future challenges2015Inngår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 44, nr Suppl 3, s. S507-S515Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ecosystem-based management (EBM) has emerged as the generally agreed strategy for managing ecosystems, with humans as integral parts of the managed system. Human activities have substantial effects on marine ecosystems, through overfishing, eutrophication, toxic pollution, habitat destruction, and climate change. It is important to advance the scientific knowledge of the cumulative, integrative, and interacting effects of these diverse activities, to support effective implementation of EBM. Based on contributions to this special issue of AMBIO, we synthesize the scientific findings into four components: pollution and legal frameworks, ecosystem processes, scale-dependent effects, and innovative tools and methods. We conclude with challenges for the future, and identify the next steps needed for successful implementation of EBM in general and specifically for the Baltic Sea.

    Fulltekst (pdf)
    fulltext
  • 41. Bonsdorff, Erik
    et al.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Elmgren, Ragnar
    Baltic Sea ecosystem-based management under climate change: Integrating social and ecological perspectives2015Inngår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 44, nr Suppl 3, s. S333-S334Artikkel i tidsskrift (Annet vitenskapelig)
    Fulltekst (pdf)
    fulltext
  • 42.
    Båmstedt, Ulf
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Wikner, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Blomqvist, Sven
    Konsekvenser för Östersjöns biologi av förändrat klimat under 21:a århundradet2007Rapport (Annet vitenskapelig)
  • 43. Creed, Irena F.
    et al.
    Bergström, Ann-Kristin
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Trick, Charles G.
    Grimm, Nancy B.
    Hessen, Dag O.
    Karlsson, Jan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Kidd, Karen A.
    Kritzberg, Emma
    McKnight, Diane M.
    Freeman, Erika C.
    Senar, Oscar E.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Ask, Jenny
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Berggren, Martin
    Cherif, Mehdi
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Giesler, Reiner
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Hotchkiss, Erin R.
    Kortelainen, Pirkko
    Palta, Monica M.
    Vrede, Tobias
    Weyhenmeyer, Gesa A.
    Global change-driven effects on dissolved organic matter composition: Implications for food webs of northern lakes2018Inngår i: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 24, nr 8, s. 3692-3714Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Northern ecosystems are experiencing some of the most dramatic impacts of global change on Earth. Rising temperatures, hydrological intensification, changes in atmospheric acid deposition and associated acidification recovery, and changes in vegetative cover are resulting in fundamental changes in terrestrial-aquatic biogeochemical linkages. The effects of global change are readily observed in alterations in the supply of dissolved organic matter (DOM)-the messenger between terrestrial and lake ecosystems-with potentially profound effects on the structure and function of lakes. Northern terrestrial ecosystems contain substantial stores of organic matter and filter or funnel DOM, affecting the timing and magnitude of DOM delivery to surface waters. This terrestrial DOM is processed in streams, rivers, and lakes, ultimately shifting its composition, stoichiometry, and bioavailability. Here, we explore the potential consequences of these global change-driven effects for lake food webs at northern latitudes. Notably, we provide evidence that increased allochthonous DOM supply to lakes is overwhelming increased autochthonous DOM supply that potentially results from earlier ice-out and a longer growing season. Furthermore, we assess the potential implications of this shift for the nutritional quality of autotrophs in terms of their stoichiometry, fatty acid composition, toxin production, and methylmercury concentration, and therefore, contaminant transfer through the food web. We conclude that global change in northern regions leads not only to reduced primary productivity but also to nutritionally poorer lake food webs, with discernible consequences for the trophic web to fish and humans.

  • 44.
    Dahlgren, Kristin
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Larsson, Ulf
    Department of Systems Ecology, Stockholm University, 10691 Stockholm, Sweden.
    Hajdu, Susanna
    Department of Systems Ecology, Stockholm University, 10691 Stockholm, Sweden.
    Båmstedt, Ulf
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Planktonic production and carbon transfer efficiency along a north-south gradient in the Baltic sea2010Inngår i: Marine Ecology Progress Series, ISSN 0171-8630, E-ISSN 1616-1599, Vol. 409, s. 77-94Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A 1 yr study was conducted along a brackish-water production gradient to enhance the understanding of factors governing pelagic food web function. This was achieved by measuring carbon transfer efficiency (TE) from the basal resource to an intermediate trophic level. TE was defined as mesozooplankton carbon consumption rate divided by production at the basal trophic level, which is composed of phytoplankton and bacteria. A north–south transect in the Baltic Sea was used as a model system, with 2 stations each in the Bothnian Bay, Bothnian Sea and Baltic Proper being sampled 5 to 8× during 2006. In addition, data from monitoring programmes were used, which comprised 10 to 22 samplings stn–1. TE was expected to be governed by the size distribution of phytoplankton and due to the nutrient gradient, we expected to find an optimal cell size, and thus also a high TE, in the intermediate-productive Bothnian Sea. The basal production during summer/autumn increased 5-fold from north to south, while the mesozooplankton carbon consumption rate exhibited a peak inthe Bothnian Sea, being ~3× higher than in both Bothnian Bay and Baltic Proper. TE was found to be intermediate in the Bothnian Bay (average: 0.8), highest in the Bothnian Sea (1.6), and lowest in the Baltic Proper (0.2). We suggest that the variation in carbon transfer efficiency can be explained by the composition of the phytoplankton community, the abundance balance between copepods and cladocerans, as well as the species composition of mesozooplankton in relation to the size structure of phytoplankton.

  • 45.
    Dahlgren, Kristin
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Eriksson Wiklund, Ann-Kristin
    Department of Applied Environmental Science, ITM, Stockholm University, 106 91 Stockholm, Sweden.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Influence of plankton structure and temperature on pelagic food web efficiency in a brackish water system2011Inngår i: Aquatic Ecology, ISSN 1386-2588, E-ISSN 1573-5125, Vol. 45, s. 307-323Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    As part of one climate change scenario, water temperature as well as the ratio between heterotrophic and autotrophic production is expected to increase; the latter at least in higher latitudes. In order to test how this scenario would affect organisms, such as metazooplankton, at higher trophic levels and carbon transfer up the food chain, a mesocosm experiment was performed at two different temperatures; 5 and 10°C, with two food webs; one phytoplankton-based (NP; autotrophic) and one bacteria-based (CNP; heterotrophic).  The groups of pelagic organisms included in the mesocosms were bacteria, flagellates, ciliates, phytoplankton and metazooplankton. Metazooplankton production was observed to increase with temperature, but was not significantly affected by food web structure. A change in food web structure, i.e. increased heterotrophy, did however lead to decreased fatty acid content and lower individual weight of the metazooplankton. Food web efficiency (FWE), defined as metazooplankton production divided by basal production, increased with autotrophy and temperature: 5CNP (0.2%) < 10CNP (0.4%) < 5NP (1.2%) < 10NP (7.3%). Our results indicate that in the climate change scenario under consideration, the temperature will have a positive effect on FWE whereas the increase in heterotrophy will have a negative effect on FWE. Furthermore, the quality, in terms of fatty acid content and individual weight of the metazooplankton, will be reduced with possible negative effects on higher trophic levels.

  • 46.
    Degerman, Rickard
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Modelling effects of river inflow of allochthonous dissolved organic carbon on coastal productionManuskript (preprint) (Annet vitenskapelig)
  • 47.
    Degerman, Rickard
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Dinasquet, Julie
    Kalmar, Sweden.
    Riemann, Lasse
    Kalmar, Sweden; Helsingör, Denmark.
    de Luna, Sara Sjostedt
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för matematik och matematisk statistik.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Effect of resource availability on bacterial community responses to increased temperature2013Inngår i: Aquatic Microbial Ecology, ISSN 0948-3055, E-ISSN 1616-1564, Vol. 68, nr 2, s. 131-142Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Climate change is predicted to cause higher temperatures and increased precipitation, resulting in increased inflow of nutrients to coastal waters in northern Europe. This has been assumed to increase the overall heterotrophy, including enhanced bacterial growth. However, the relative importance of temperature, resource availability and bacterial community composition for the bacterial growth response is poorly understood. In the present study, we investigated effects of increased temperature on bacterial growth in waters supplemented with different nutrient concentrations and inoculated with microbial communities from distinct seasonal periods. Seven experiments were performed in the northern Baltic Sea spanning an entire annual cycle. In each experiment, bacterioplankton were exposed to 2 temperature regimes (in situ and in situ + 4 degrees C) and 5 nutrient concentrations. Generally, elevated temperature and higher nutrient levels caused an increase in the bacterial growth rate and a shortening of the response time (lag phase). However, at the lowest nutrient concentration, bacterial growth was low at all tested temperatures, implying a stronger dependence on resource availability than on temperature for bacterial growth. Furthermore, data indicated that different bacterial assemblages had varying temperature responses and that community composition was strongly affected by the combination of high nutrient addition and high temperature. These results support the concern that climate change will promote heterotrophy in aquatic systems, where nutrient levels will increase considerably. In such environments, the bacterial community composition will change, their growth rates will increase, and their response time will be shortened compared to the present situation.

    Fulltekst (pdf)
    Effect of resource availability on bacterial community responses to increased temperature
  • 48.
    Degerman, Rickard
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Lefébure, Robert
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Byström, Pär
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Båmstedt, Ulf
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Larsson, Stefan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Food web interactions determine energy transfer efficiency and top consumer responses to inputs of dissolved organic carbon2018Inngår i: Hydrobiologia, ISSN 0018-8158, E-ISSN 1573-5117, Vol. 805, nr 1, s. 131-146Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Climate change projections indicate increased precipitation in northern Europe, leading to increased inflow of allochthonous organic matter to aquatic systems. The food web responses are poorly known, and may differ depending on the trophic structure. We performed an experimental mesocosm study where effects of labile dissolved organic carbon (DOC) on two different pelagic food webs were investigated, one having zooplankton as highest trophic level and the other with planktivorous fish as top consumer. In both food webs, DOC caused higher bacterial production and lower food web efficiency, i.e., energy transfer efficiency from the base to the top of the food web. However, the top-level response to DOC addition differed in the zooplankton and the fish systems. The zooplankton production increased due to efficient channeling of energy via both the bacteria land the phytoplankton pathway, while the fish production decreased due to channeling of energy mainly via the longer and less efficient bacterial pathway. We conclude that the added DOC either acted as a subsidy by increasing the production of the top trophic level (mesozooplankton), or as a sink causing decreased top consumer production (planktivorous fish).

    Fulltekst (pdf)
    fulltext
  • 49. Ejsmond, M. J.
    et al.
    Blackburn, N.
    Fridolfsson, E.
    Haecky, P.
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Casini, M.
    Belgrano, A.
    Hylander, S.
    Modeling vitamin B1 transfer to consumers in the aquatic food web2019Inngår i: Scientific Reports, E-ISSN 2045-2322, Vol. 9, artikkel-id 10045Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Vitamin B-1 is an essential exogenous micronutrient for animals. Mass death and reproductive failure in top aquatic consumers caused by vitamin B-1 deficiency is an emerging conservation issue in Northern hemisphere aquatic ecosystems. We present for the first time a model that identifies conditions responsible for the constrained flow of vitamin B-1 from unicellular organisms to planktivorous fishes. The flow of vitamin B-1 through the food web is constrained under anthropogenic pressures of increased nutrient input and, driven by climatic change, increased light attenuation by dissolved substances transported to marine coastal systems. Fishing pressure on piscivorous fish, through increased abundance of planktivorous fish that overexploit mesozooplankton, may further constrain vitamin B-1 flow from producers to consumers. We also found that key ecological contributors to the constrained flow of vitamin B-1 are a low mesozooplankton biomass, picoalgae prevailing among primary producers and low fluctuations of population numbers of planktonic organisms.

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  • 50. Elmgren, Ragnar
    et al.
    Blenckner, Thorsten
    Andersson, Agneta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Baltic Sea management: Successes and failures2015Inngår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 44, nr Suppl 3, s. S335-S344Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    Severe environmental problems documented in the Baltic Sea in the 1960s led to the 1974 creation of the Helsinki Convention for the Protection of the Marine Environment of the Baltic Sea Area. We introduce this special issue by briefly summarizing successes and failures of Baltic environmental management in the following 40 years. The loads of many polluting substances have been greatly reduced, but legacy pollution slows recovery. Top predator populations have recovered, and human exposure to potential toxins has been reduced. The cod stock has partially recovered. Nutrient loads are decreasing, but deep-water anoxia and cyanobacterial blooms remain extensive, and climate change threatens the advances made. Ecosystem-based management is the agreed principle, but in practice the various environmental problems are still handled separately, since we still lack both basic ecological knowledge and appropriate governance structures for managing them together, in a true ecosystem approach.

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