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  • 1.
    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 Regions2019Ingår i: Environmental Science: Processes & Impacts, ISSN 2050-7887, E-ISSN 2050-7895, s. 881-892Artikel i tidskrift (Refereegranskat)
    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.

  • 2. Brett, Michael T.
    et al.
    Bunn, Stuart E.
    Chandra, Sudeep
    Galloway, Aaron W. E.
    Guo, Fen
    Kainz, Martin J.
    Kankaala, Paula
    Lau, Danny C. P.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Moulton, Timothy P.
    Power, Mary E.
    Rasmussen, Joseph B.
    Taipale, Sami J.
    Thorp, James H.
    Wehr, John D.
    How important are terrestrial organic carbon inputs for secondary production in freshwater ecosystems?2017Ingår i: Freshwater Biology, ISSN 0046-5070, E-ISSN 1365-2427, Vol. 62, nr 5, s. 833-853Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    1. Many freshwater systems receive substantial inputs of terrestrial organic matter. Terrestrially derived dissolved organic carbon (t-DOC) inputs can modify light availability, the spatial distribution of primary production, heat, and oxygen in aquatic systems, as well as inorganic nutrient bioavailability. It is also well-established that some terrestrial inputs (such as invertebrates and fruits) provide high-quality food resources for consumers in some systems. 2. In small to moderate-sized streams, leaf litter inputs average approximately three times greater than the autochthonous production. Conversely, in oligo/mesotrophic lakes algal production is typically five times greater than the available flux of allochthonous basal resources. 3. Terrestrial particulate organic carbon (t-POC) inputs to lakes and rivers are comprised of 80%-90% biochemically recalcitrant lignocellulose, which is highly resistant to enzymatic breakdown by animal consumers. Further, t-POC and heterotrophic bacteria lack essential biochemical compounds that are critical for rapid growth and reproduction in aquatic invertebrates and fishes. Several studies have directly shown that these resources have very low food quality for herbivorous zooplankton and benthic invertebrates 4. Much of the nitrogen assimilated by stream consumers is probably of algal origin, even in systems where there appears to be a significant terrestrial carbon contribution. Amino acid stable isotope analyses for large river food webs indicate that most upper trophic level essential amino acids are derived from algae. Similarly, profiles of essential fatty acids in consumers show a strong dependence on the algal food resources. 5. Primary production to respiration ratios are not a meaningful index to assess consumer allochthony because respiration represents an oxidised carbon flux that cannot be utilised by animal consumers. Rather, the relative importance of allochthonous subsidies for upper trophic level production should be addressed by considering the rates at which terrestrial and autochthonous resources are consumed and the growth efficiency supported by this food. 6. Ultimately, the biochemical composition of a particular basal resource, and not just its quantity or origin, determines how readily this material is incorporated into upper trophic level consumers. Because of its highly favourable biochemical composition and greater availability, we conclude that microalgal production supports most animal production in freshwater ecosystems.

  • 3.
    Grieve, Adrian
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Lau, Danny C. P.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Do autochthonous resources enhance trophic transfer of allochthonous organic matter to aquatic consumers, or vice versa?2018Ingår i: Ecosphere, ISSN 2150-8925, E-ISSN 2150-8925, Vol. 9, nr 6, artikel-id e02307Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Autochthonous and allochthonous resources are known to differ in nutritional quality and trophic support for aquatic food webs, but it is less clear how these high- and low-quality resources interact to affect trophic transfer and consumer production. We conducted 30-d feeding trials to investigate the resource assimilation, somatic growth, and fatty-acid (FA) composition of the widespread benthic generalist isopod Asellus aquatints, in response to different ratios of low-quality allochthonous (leaf litter) to high-quality autochthonous diets (algae). Wet mass growth of Asellus was lowest when fed 100% leaf litter or algae (0.53 +/- 0.46 and 0.55 +/- 0.57 mg center dot g(-1)center dot d(-1), respectively; mean +/- SE) and highest (4.95 +/- 0.51 mg center dot g(-1)center dot d(-1)) with a diet of 90:10 leaf litter:algae ratio. Asellus tended to grow slower with increasing dietary algal proportions (10-100%), yet stable isotopes and Bayesian mixing models revealed consistently high algal assimilation (>= 94%) by Asellus. Therefore, among the mixed-diet treatments, Asellus biomass production using algal resources was optimized when terrestrial organic matter (OM) dominated over algae. Eicosapentaenoic acid (EPA):total FA, EPA:omega-3 FA, and arachidonic acid:total FA declined, but docosahexaenoic acid (DHA):omega-3 FA increased, with increasing growth of Asellus. Tissue EPA concentrations of Asellus were similar among treatments, so reductions in EPA:omega-3 and EPA:total FA were due to increases in DHA concentration. Overall, our results suggest synergistic effects between autochthonous and allochthonous resources on Asellus growth and that allochthonous OM particularly facilitates the trophic transfer of autochthonous resources. Asellus preferentially retains DHA at low algal availability. This may improve its neural tissue development and so its success in accessing algae. The growth and FA responses of the widespread Asellus can enhance resource and DHA transfer to visual predators that have greater DHA demands, particularly when brownification of boreal freshwaters likely intensifies upon global climate change.

  • 4.
    Kupryianchyk, Darya
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Giesler, Reiner
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Bidleman, Terry F.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Liljelind, Per
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Lau, Danny Chun Pong
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Sponseller, Ryan A.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Andersson, Patrik L.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Industrial and natural compounds in filter-feeding black fly larvae and water in 3 tundra streams2018Ingår i: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 37, nr 12, s. 3011-3017Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report concentrations of polychlorinated biphenyls, polybrominated diphenyl ethers, novel flame retardants, and naturally occurring bromoanisoles in water and filter-feeding black fly (Simuliidae) larvae in 3 tundra streams in northern Sweden. The results demonstrate that black fly larvae accumulate a wide range of organic contaminants and can be used as bioindicators of water pollution in Arctic streams.

  • 5.
    Lau, Danny C. P.
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Vrede, Tobias
    Goedkoop, Willem
    Lake responses to long-term disturbances and management practices2017Ingår i: Freshwater Biology, ISSN 0046-5070, E-ISSN 1365-2427, Vol. 62, nr 4, s. 792-806Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    1. Long-term human-induced disturbances such as acidification and algal invasions, and management practices such as liming, are known to alter community structure and biodiversity of north temperate lakes. We assessed if they impacted on the trophic ecology and production of apex consumers (i.e. fish) and the overall food-chain length (FCL) of boreal lake ecosystems, and if these functional responses were consistent with the biodiversity changes. We hypothesise that fish production and FCL decrease with decreasing species biodiversity of lake communities, and that long-term environmental perturbations will alter the relative reliance of fish on littoral versus pelagic trophic pathways and their ontogenetic changes in trophic position (TP). 2. We analysed long-term data and stable isotopes of multiple organismal groups - phytoplankton, zooplankton, littoral and sub-littoral/profundal macroinvertebrates, and fish - collected from small boreal lakes that have been subjected to acidification, lime application and/or algal invasion by Gonyostomum semen. Species biodiversity, FCL and fish production (i.e. growth and catch-per-uniteffort) were compared among three lake categories, i.e. acidic, limed and circumneutral (reference) lakes, within each three lakes were selected. Fish TP and their relative littoral versus pelagic reliance were estimated based on stable nitrogen and carbon isotopes respectively. 3. Gonyostomum contributed to 77-98% phytoplankton biovolume in acidic lakes, <1-79% in limed lakes and 0-30% in circumneutral lakes. Its prevalence was correlated with total organic carbon concentration but not with lake pH, alkalinity or any other environmental variable. Diversity and evenness of phytoplankton, macroinvertebrates and fish generally decreased with increasing Gonyostomum biovolume, such that biodiversity was higher in circumneutral and limed lakes than in acidic lakes. 4. Isotopic data revealed that FCL was shortest in limed lakes (3.94 +/- 0.08; least- squares mean +/- SE), intermediate in acidic lakes (4.19 +/- 0.07) and longest in circumneutral lakes (4.38 +/- 0.08). Limed lakes also had the lowest fish growth and CPUE. Overall littoral reliance of fish was higher in acidic lakes (0.53 +/- 0.03) than in limed lakes (0.42 +/- 0.02) and circumneutral lakes (0.30 +/- 0.02), suggesting that fish production and FCL there could have been sustained by the increased littoral reliance when pelagic trophic pathways were hindered by Gonyostomum invasion. European perch (Perca fluviatilis), the most common fish in the lakes, showed faster TP increases in acidic and limed lakes, likely due to their earlier ontogenetic shift from zooplanktivory to zoobenthivory and/or piscivory. 5. Overall, our findings indicate that long-term disturbances (i.e. acidification and algal invasions) and management practices (i.e. liming) can (i) induce contrasting responses in biodiversity, FCL and fish production of boreal lakes; (ii) be the primary driver of FCL variation among small and similar-size ecosystems; and (iii) alter the trophic ecology (i.e. TP change during ontogeny and littoral reliance) of key fish species. The trophic ecology and production of apex consumers and FCL together can provide useful integrated proxies for ecosystem functioning, which can supplement traditional biodiversity measurements for more robust environmental assessments.

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