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  • 301.
    Larsson, Per
    et al.
    Department of Ecology, Limnology, University of Lund.
    Södergren, A
    Transport of polychlorinated biphenyls (PCBs) in freshwater mesocosms from sediment to water and air1987In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 36, p. 33-46Article in journal (Refereed)
    Abstract [en]

    With sediment as a source the flux of PCBs to water and air was followed in mesocosms with and without fish for two vegetation seasons. The fish represented the largest lipid pool in the mesocosm, and their presence increased the flux of PCBs across the sediment/water interface. The flow of PCBs from sediment to water followed a seasonal pattern with higher rates during summer than in the winter. The rates were governed by the turbation activity of benthic invertebrates, the extent of gas production in the sediment, the amount and quality of the lipid pools in the water column, and the solubility of the PCBs. The greatest amount of PCBs among the lipid pools was found in the dissolved extractable lipids, which also showed the highest concentration of PCBs calculated on a lipid basis. After about 1.5 yr, >90% of the PCBs added was still in the sediment. The remainder was distributed within the mesocosms to various extents depending on the amount and quality of the lipid pools, or transferred into the air. Transfer into the air was governed by PCB concentrations in the water, and by water temperature. The flow was highest during summer, when the surface microlayer renewed its load of PCBs every 8th day. 

  • 302.
    Larsson, Per
    et al.
    Lund university.
    Södergren, Anders
    Lund university.
    In which ways are persistent, organic compounds transportedin the environment?1982In: Förekomst och effekter av persistenta organiska ämnen i miljön: projektområdeskonferens, Wenner-Gren center, Stockholm den 9 mars 1982 / [ed] Niklas Johansson, Solna: Statens naturvårdsverk , 1982, , p. 35-51p. 35-51Chapter in book (Other academic)
  • 303.
    Larsson, Per
    et al.
    Department of Ecology, Limnology Section, University of Lund.
    Thurén, A
    Di-2-ethylhexylphthalate inhibits the hatching of frog eggs and is bioaccumulated by tadpoles1987In: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 6, no 6, p. 417-422Article in journal (Refereed)
    Abstract [en]

    Frog eggs were exposed to di-2-ethylhexylphthalate (DEHP) added to the sediment in laboratory model systems. The number of successful hatchings decreased as the DEHP concentration was increased. In tadpoles, the uptake was concentration-dependent. The phthalate ester was transported from the sediment to the water, and the extent of the transport was governed by levels of DEHP in the sediment. Our results show that the reproduction of frogs may be negatively affected in aquatic environments polluted with phthalates. 

  • 304.
    Larsson, Per
    et al.
    UNIV LUND, INST LIMNOL.
    Thurén, A
    Gahnström, G
    Phthalate esters inhibit microbial activity in aquatic sediments1986In: Environmental pollution, ISSN 0143-1471, Vol. 42, no 3, p. 223-231Article in journal (Refereed)
    Abstract [en]

    Sediments were exposed to five concentrations of the plasticizer di(2-ethylhexyl)phthalate (DEHP) and the effects on sediments oxygen uptake were assessed. The sediments were taken from an eutrophic lake and consisted of 'undisturbed' sediment with overlying lake water. The community respiration in the sediment was inhibited by DEHP. The oxygen uptake from uncontaminated sediment was significantly higher than from sediments containing DEHP. The decrease in microbial activity in contaminated sediment cores was positively correlated to increasing levels of DEHP in the sediment. At concentrations of 25 μg DEHP g−1 and higher the sediment respiration consisted of chemical, rather than biological, oxygen consumption. 

  • 305.
    Larsson, Per
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Tibblin, Petter
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Koch-Schmidt, Per
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Engstedt, Olof
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Nilsson, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Nordahl, Oscar
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Forsman, Anders
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Ecology, evolution, and management strategies of northern pike populations in the Baltic Sea2015In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 44, no Supplement 3, p. S451-S461Article, review/survey (Refereed)
    Abstract [en]

    Baltic Sea populations of the northern pike (Esox lucius) have declined since the 1990s, and they face additional challenges due to ongoing climate change. Pike in the Baltic Sea spawn either in coastal bays or in freshwater streams and wetlands. Pike recruited in freshwater have been found to make up about 50 % of coastal pike stocks and to show natal homing, thus limiting gene flow among closely located spawning sites. Due to natal homing, sub-populations appear to be locally adapted to their freshwater recruitment environments. Management actions should therefore not involve mixing of individuals originating from different sub-populations. We offer two suggestions complying with this advice: (i) productivity of extant freshwater spawning populations can be boosted by modifying wetlands such that they promote spawning and recruitment; and (ii) new sub-populations that spawn in brackish water can potentially be created by transferring fry and imprinting them on seemingly suitable spawning environments.

  • 306.
    Larsson, Per
    et al.
    Limnology, Department of Ecology, University of Lund .
    Woin, P
    Knulst, J
    Differences in uptake of pesistent pollutants for predators feeding in aquatic and terrestrial habitats1990In: Holarctic ecology, ISSN 0105-9327, Vol. 13, p. 149-155Article in journal (Refereed)
    Abstract [en]

    Persistent pollutants in mustelid species( e.g. otter, mink, marten) were investigated. For a given animal, concentration of PCB and DDT in muscle were correlated with concentrations in its anal gland secretion. The correlation suggests that small samples of secretion could be used for pollutant analysis thereby eliminating the need to sacrifice animals. There was also a correlation between muscle and liver concentrations of these compounds, indicating a partitioning between different organs. Furthermore we showed that habitat differences between species led to interspecific variation in the uptake of persistent pollutants. Mink, which mainly feed in aquatic environments contained a higher proportion of p,p-DDT than marten, which feeds on terrestrial prey. Differences in PCB uptake were also noted between the two predators, though the congener distribution was heavily domined by a few hexa- and heptachlorobiphenyls. 

  • 307.
    Leberfinger, Karolina
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Revealing the role of shredders and detritus in open-canopy, intermittent streams2010Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Many streams run through naturally-unforested, agricultural, and residential landscapes and thus do not have closed riparian canopies. Little is known of food web dynamics and ecosystem function in such open-canopy streams. Similarly, our knowledge of ecosystem processes in intermittent streams and effects of drought on stream ecosystem function are limited, despite that predictions of climate change effects include increased frequency and duration of droughts in freshwaters. The aim of my thesis was to increase our knowledge of invertebrate shredder assemblages and ecosystem function in open-canopy intermittent streams and to reveal the role of terrestrial organic matter in open-canopy streams. Invertebrate shredders, as primary consumers of detritus, significantly contribute to the ecosystem function decomposition of organic matter. Thereby, shredders are important vectors for transferring detrital energy into stream food webs.

    I found high-density and species-rich shredder assemblages in three open-canopy intermittent streams on the island of Öland in the southern Baltic Sea, Sweden. My results showed that terrestrially derived organic matter was the shredder’s main food source and the amount of high-quality CPOM potentially limited shredder production. However, through supplementing their feeding with algae, a high shredder production, similar to production estimates in forested permanent streams, could be maintained in these open-canopy intermittent streams. Instead, my results indicate that the primary physical factor constraining shredder production in intermittent streams is the length of the summer drought period. Furthermore, drying simulated as decreasing water levels in an experiment, decreased invertebrate shredder feeding activity and consequently, the breakdown rate of organic matter. Drying also altered a caddisfly shredders’ life cycle phenology and such evident induction of earlier pupation due to drying has not been shown for aquatic insects earlier.

    Food webs and ecosystem function and processes in open-canopy and intermittent streams deserve further attention, especially as these types of streams are very common worldwide. My findings indicate that the energy base in open-canopy streams may be terrestrially derived organic matter, as in forested streams, but constraints imposed by habitat traits and differences in organic matter input size may have significant consequences on stream productivity. My results may be important for increased understanding of potential effects of land use changes (i.e. forestry, agriculture, urbanization) and environmental changes (i.e. climate change) on stream ecosystems.

  • 308.
    Leberfinger, Karolina
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Bohman, Irene
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Grass, mosses, algae or leaves? Food preference among shredders from open-canopy streams2010In: Aquatic Ecology, ISSN 1386-2588, E-ISSN 1573-5125, Vol. 44, no 1, p. 195-203Article in journal (Refereed)
    Abstract [en]

    Shredder feeding is a vital process in making decomposition products available to biota in streams. To investigate which food sources shredders in open-canopy streams exploit, we conducted a feeding preference experiment with the invertebrate detritivores Limnephilus bipunctatus and Nemoura sp., which are commonly found in open-canopy streams on the Swedish island of A-land in the southern Baltic Sea. Leaves of birch, Swedish whitebeam, and shrubby cinquefoil; dead and fresh grass; water moss; and algae were offered to the shredders in multi- and single treatments. We hypothesized that food with high nutritional value would be preferred. Both taxa preferred leaves of shrubby cinquefoil, a bush common in the riparian zone of A-land streams; additionally Nemoura sp. also chose algae. Dead grass, the most abundant food source in the streams during the whole year, was the least consumed food type. The fresh food types had highest nutritional value, measured as carbon to nitrogen content. Therefore, food quality could not alone explain the preference of shrubby cinquefoil. However, among the detritus type offered, shrubby cinquefoil had the highest nutritional value. Shrubby cinquefoil may constitute one important energy source to these open-canopy stream ecosystems and may be essential in maintaining an abundant shredder community in these streams. Thus, the results of this study indicate that detrital resources are indeed important in open-canopy stream systems.

  • 309.
    Leberfinger, Karolina
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Bohman, Irene
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Herrmann, Jan
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Drought impact on stream detritivores - experimental effects on leaf litter breakdown and life cycles2010In: Hydrobiologia, ISSN 0018-8158, E-ISSN 1573-5117, Vol. 652, no 1, p. 247-254Article in journal (Refereed)
    Abstract [en]

    Predictions of effects of global climate change include decreased runoff for many parts of the world, which will result in drying of streams. Information of the effects of drought on aquatic ecosystems is limited and little is known of the effects on ecosystem functions. Our main objective was to measure the direct effects of drought on leaf litter breakdown by invertebrate shredders in a controlled laboratory experiment. We hypothesized a decreased breakdown at high drought level. Single-species and multi-species treatments with three shredder species (Asellus aquaticus, Limnephilus bipunctatus, and L. flavicornis) were set up in an experiment with three drought level treatments, control, medium, and high drought (6 cm water level, 1 cm water level, and water level below sediment surface, respectively). Breakdown measured as leaf litter loss was significantly lower in both medium and high drought treatments compared to the control. Previously, decreased breakdown due to drying has been reported, but attributed to low densities of invertebrate shredders. We show that even when shredders are present, drought decreases the breakdown. Drought treatments also induced earlier pupation for the caddisfly L. flavicornis. Shifts in species phenology due to drought, e.g., earlier emergence, may affect species ability to adult survival and reproduction. Shifts in timing of emergence may also affect terrestrial food webs, where emerging aquatic insects may constitute an important food subsidy. Our knowledge of the complex effects of droughts in aquatic systems is limited with an urgent need of extended knowledge of the ecological effects of droughts on freshwater ecosystem functioning.

  • 310.
    Leberfinger, Karolina
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Bohman, Irene
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Herrmann, Jan
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    The importance of terrestrial resource subsidies for shredders in open-canopy streams revealed by stable isotope analysis2011In: Freshwater Biology, ISSN 0046-5070, E-ISSN 1365-2427, Vol. 56, no 3, p. 470-480Article in journal (Refereed)
    Abstract [en]

    1. Allochthonous detritus is the major source of energy in forested streams, but less is known of the importance of terrestrial subsidies to open-canopy streams. Here, we used stable isotope analysis to assess the importance of allochthonous versus autochthonous energy sources to invertebrate shredders in four open-canopy streams in Sweden. Shredders and potential food sources were analysed at both open sites and those with deciduous trees in the riparian zone.2. Mixing models showed that allochthonous coarse particulate organic matter was the most important energy source to shredders at both the open and wooded sites, suggesting that terrestrial subsidies may be an important process in open-canopy streams, just as they are in forested streams.3. However, shredders at open sites had a larger proportion of biofilm in their diet than at wooded sites, indicating an ability of shredders to adjust their diet with food availability.4. We also used the carbon and nitrogen stable isotope signatures to assess the size of the feeding niche of shredders. Feeding on both allochthonous and autochthonous sources at open sites was reflected in a larger feeding niche than at wooded sites for one of the three species analysed. There was substantial overlap of the feeding niche among shredder species, indicating a high functional redundancy within this guild.

  • 311.
    Leberfinger, Karolina
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Herrmann, Jan
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Secondary production of invertebrate shredders in open-canopy, intermittent streams on the island of Öland, SE Sweden2010In: Journal of The North American Benthological Society, ISSN 0887-3593, E-ISSN 1937-237X, Vol. 29, p. 934-944Article in journal (Refereed)
    Abstract [en]

    Knowledge of functional aspects of communities in intermittent streams currently is lacking, and the role of terrestrial detritus as a resource in open-canopy streams is uncertain. Our main objective was to characterize and quantify the macroinvertebrate shredder assemblages in 3 intermittent open-canopy streams on the island of Öland in the Baltic Sea, Sweden, by estimating secondary production. Estimates of annual shredder secondary production ranged from 0.005 to 13.6 g ash-free dry mass (AFDM) m−2 y−1 among sites. Shredder production and amount of organic matter were positively related, but shredder production was more strongly influenced by the duration of the summer dry period. Production decreased with increase in the length of the summer dry period, but shredder production was still high at sites with long dry phases and was comparable to estimates of shredder production in permanent forested streams, results suggesting that terrestrial organic matter might be an important energy resource in open-canopy streams. Shredder species richness decreased with increase in length of the summer dry phase, and shredder species composition at sites with a long dry period was dominated by drought-tolerant taxa. Our results suggest that ecosystem functions might shift from being sustained by many taxa to being sustained by fewer taxa as stream ecosystems experience moderate droughts of similar length (2–4 mo).

  • 312.
    Leberfinger, Karolina
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Herrmann, Jan
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Spatial and temporal distribution of shredders in leaf-limited intermittent streams2010In: Verhandlungen Internat. Verein. Limnol 30, Stuttgart: E. Schweizerbart'sche Verlagsbuchhandlung, 2010, p. 1342-1344Conference paper (Refereed)
  • 313.
    Leberfinger, Karolina
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Herrmann, Jan
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Hoover, Trent M.
    University of British Columbia.
    Bohman, Irene
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Richardson, John S.
    University of British Columbia.
    Modelling climatic change effects of decomposition processes in small streamsManuscript (preprint) (Other academic)
  • 314.
    Lebret, Karen
    et al.
    Lund University.
    Fernandez, Maria Fernandez
    Hagman, Camilla H. C.
    Rengefors, Karin
    Hansson, Lars-Anders
    Grazing resistance allows bloom formation and may explain invasion success of Gonyostomum semen2012In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 57, no 3, p. 727-734Article in journal (Refereed)
    Abstract [en]

    The nuisance alga Gonyostomum semen (Raphidophyceae) has expanded in the Nordic countries during the last decades and can dominate lake phytoplankton communities almost completely. A possible explanation to its dominance could be limited grazing by zooplankton. We investigated the potential grazing pressure on G. semen using an experimental approach supported by field data. We determined the grazing rate by cladocerans, calanoid copepods, and Chaoborus larvae to determine which were able to feed on G. semen. Only the large cladoceran Daphnia magna was able to feed successfully on G. semen. The large cell size of G. semen was likely a limiting factor for the filtering apparatus of smaller cladocerans. The copepod Eudiaptomus gracilis did not graze on G. semen, although the mechanism behind this selective feeding is still unknown. In addition to the experimental study, we quantified the zooplankton and phytoplankton communities in 40 lakes to determine the composition and abundance of the zooplankton communities co-occurring with G. semen, suggesting that large cladoceran species were not present in lakes where G. semen occurred. Hence, the growth of G. semen is not significantly controlled by grazing in natural systems, which likely facilitates bloom formation and invasion success of G. semen.

  • 315.
    Lebret, Karen
    et al.
    Lund University.
    Kritzberg, Emma S.
    Figueroa, Rosa
    Rengefors, Karin
    Genetic diversity within and genetic differentiation between blooms of a microalgal species2012In: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920, Vol. 14, no 9, p. 2395-2404Article in journal (Refereed)
    Abstract [en]

    The field of genetic diversity in protists, particularly phytoplankton, is under expansion. However, little is known regarding variation in genetic diversity within populations over time. The aim of our study was to investigate intrapopulation genetic diversity and genetic differentiation in the freshwater bloom-forming microalga Gonyostomum semen (Raphidophyceae). The study covered a 2-year period including all phases of the bloom. Amplified fragment length polymorphism (AFLP) was used to determine the genetic structure and diversity of the population. Our results showed a significant differentiation between samples collected during the two blooms from consecutive years. Also, an increase of gene diversity and a loss of differentiation among sampling dates were observed over time within a single bloom. The latter observations may reflect the continuous germination of cysts from the sediment. The life cycle characteristics of G. semen, particularly reproduction and recruitment, most likely explain a high proportion of the observed variation. This study highlights the importance of the life cycle for the intraspecific genetic diversity of microbial species, which alternates between sexual and asexual reproduction.

  • 316.
    Lebret, Karen
    et al.
    Lund University.
    Kritzberg, Emma S.
    Lund University.
    Rengefors, Karin
    Lund University.
    Population Genetic Structure of a Microalgal Species under Expansion2013In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 8, no 12, p. e82510-Article in journal (Refereed)
    Abstract [en]

    Biological invasions often cause major perturbations in the environment and are well studied among macroorganisms. Less is known about invasion by free-living microbes. Gonyostomum semen (Raphidophyceae) is a freshwater phytoplankton species that has increased in abundance in Northern Europe since the 1980's and has expanded its habitat range. In this study, we aimed to determine the genetic population structure of G. semen in Northern Europe and to what extent it reflects the species' recent expansion. We sampled lakes from 12 locations (11 lakes) in Norway, Sweden and Finland. Multiple strains from each location were genotyped using Amplified Fragment Length Polymorphism (AFLP). We found low differentiation between locations, and low gene diversity within each location. Moreover, there was an absence of genetic isolation with distance (Mantel test, p = 0.50). According to a Bayesian clustering method all the isolates belonged to the same genetic population. Together our data suggest the presence of one metapopulation and an overall low diversity, which is coherent with a recent expansion of G. semen.

  • 317.
    Lebret, Karen
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Uppsala University.
    Langenheder, Silke
    Uppsala University.
    Colinas, Noemi
    Uppsala University.
    Östman, Örjan
    Swedish University of Agricultural Sciences.
    Lindström, Eva S.
    Uppsala University.
    Increased water colour affects freshwater plankton communities in a mesocosm study2018In: Aquatic Microbial Ecology, ISSN 0948-3055, E-ISSN 1616-1564, Vol. 81, no 1, p. 1-17Article in journal (Refereed)
    Abstract [en]

    Increases in water colour (brownification) have been observed in aquatic systems in the Northern Hemisphere, partly caused by increased loading of organic carbon from terrestrial origins. We investigated the effect of increase in water colour on the composition, structure and function of lake plankton communities (bacteria, phytoplankton and zooplankton) conducting a mesocosm experiment in 3 medium-coloured lakes (average absorbance at 420 nm: 0.034 cm(-1)), with different nutrient concentrations and phytoplankton community composition. To simulate an increase in water colour, we added humic substances (HuminFeed) at 3 different concentrations. The additions significantly affected the water colour of the mesocosms, but had no measurable effect on total organic carbon concentration, thus change in light conditions was the main effect of our treatment on the plankton communities. The increase in water colour did not significantly affect the measured functions (productivity, respiration) and biomass of the plankton communities (bacteria, phytoplankton and zooplankton), but led to changes in the relative abundance of some phytoplankton taxa and, to a lesser extent, the bacterial community (differences in relative abundance). The treatments had no significant effect on zooplankton biomass or composition. Our study suggests that increases in water colour favour low-light-adapted phytoplankton species, which in turn also can affect bacterial composition, whereas the change in light climate had no clear impact on the functioning of plankton communities in weakly humic lakes.

  • 318.
    Lebret, Karen
    et al.
    Lund University.
    Tesson, Sylvie V. M.
    Lund University.
    Kritzberg, Emma S.
    Lund University.
    Tomas, Carmelo
    University of North Carolina at Wilmington, USA.
    Rengefors, Karin
    Lund University.
    Phylogeography of the freshwater raphidophyte Gonyostomum semen confirms a recent expansion in northern Europe by a single haplotype2015In: Journal of Phycology, ISSN 0022-3646, E-ISSN 1529-8817, Vol. 51, no 4, p. 768-781Article in journal (Refereed)
    Abstract [en]

    Gonyostmum semen is a freshwater raphidophyte that has increased in occurrence and abundance in several countries in northern Europe since the 1980s. More recently, the species has expanded rapidly also in north-eastern Europe, and it is frequently referred to as invasive. To better understand the species history, we have explored the phylogeography of G. semen using strains from northern Europe, United States, and Japan. Three regions of the ribosomal RNA gene (small subunit [SSU], internal transcribed spacer [ITS] and large subunit [LSU]) and one mitochondrial DNA marker (cox1) were analyzed. The SSU and partial LSU sequences were identical in all strains, confirming that they belong to the same species. The ITS region differentiated the American from the other strains, but showed high intra-strain variability. In contrast, the mitochondrial marker cox1 showed distinct differences between the European, American, and Japanese strains. Interestingly, only one cox1 haplotype was detected in European strains. The overall low diversity and weak geographic structure within northern European strains supported the hypothesis of a recent invasion of new lakes by G. semen. Our data also show that the invasive northern European lineage is genetically distinct from the lineages from the other continents. Finally, we concluded that the mitochondrial cox1 was the most useful marker in determining large-scale biogeographic patterns in this species.

  • 319.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Algae in Småland and the islands: high value products and waste-to-energy conversion solutions2014In: Presented at CementaHeidelberg, Burglengenfeld, Germany, October 2-3, 2014, 2014Conference paper (Other academic)
  • 320.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Algae in Småland and the islands: High value products and waste-to-energy conversion solutions2014Conference paper (Other (popular science, discussion, etc.))
  • 321.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Algoland: industry and ecology together2018In: Presented at the 1st Nordic Algae Symposium 2018 (NAS18), Helsinki, Finland, January 31, 2018, 2018Conference paper (Other academic)
  • 322.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Algoland Workshop: business models2018In: Algoland 2030 Workshop, Kalmar, Sweden, April 24, 2018, 2018Conference paper (Other academic)
  • 323.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Think About Our Environment2015Conference paper (Other (popular science, discussion, etc.))
  • 324.
    Legrand, Catherine
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Casotti, Raffaella
    Stazione Zoologica Anton Dohrn, Napoli, Italy.
    Climate-induced changes and Harmful Algal Blooms in the Mediterranean Sea: Perspectives on future scenarios2009In: CIESM workshop monograph series : Phytoplankton responses to Mediterranean environmental changes, Tunis (Tunisia) 7-10 October 2009, ISSN 1726-5886, no 40, p. 63-66Article, review/survey (Refereed)
  • 325.
    Legrand, Catherine
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Hussenot, J
    Rincé, Y
    Joassard, L
    Mornet, F
    Pirastru, L
    Mass production of microalgae in salt ponds (L Houmeau, France) with farm fertilizer di-ammonium phosphate in addition with silicon1991In: EAS Special Publication 14, 1991, p. 187-188Conference paper (Refereed)
  • 326.
    Legrand, Catherine
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Lindehoff, Elin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Olofsson, Martin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Mikroalgers potential inom biofiltering av industriell rökgas och processvatten2014Conference paper (Other (popular science, discussion, etc.))
  • 327.
    Lehtonen, Topi K.
    et al.
    Monash Univ, Australia.
    Svensson, P. Andreas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Monash Univ, Australia.
    Wong, Bob B. M.
    Monash Univ, Australia.
    Aggressive desert goby males also court more, independent of the physiological demands of salinity2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 9352Article in journal (Refereed)
    Abstract [en]

    Both between- and within-individual variation in behaviour can be important in determining mating opportunities and reproductive outcomes. Such behavioural variability can be induced by environmental conditions, especially if individuals vary in their tolerance levels or resource allocation patterns. We tested the effects of exposure to different salinity levels on male investment into two important components of mating success-intrasexual aggression and intersexual courtship-in a fish with a resource defence mating system, the desert goby, Chlamydogobius eremius. We found that males that were more aggressive to rivals also exhibited higher rates of courtship displays towards females. Contrary to predictions, this positive relationship, and the consistency of the two behaviours, were not affected by the salinity treatment, despite the physiological costs that high salinity imposes on the species. Moreover, over the entire data-set, there was only a marginally non-significant tendency for males to show higher levels of aggression and courtship in low, than high, salinity. The positive correlation between male aggression and courtship, independent of the physiological demands of the environment, suggests that males are not inclined to make contrasting resource investments into these two key reproductive behaviours. Instead, in this relatively euryhaline freshwater species, typical investment into current reproductive behaviours can occur under a range of different salinity conditions.

  • 328.
    Lehtonen, Topi K.
    et al.
    University of Konstanz, Germany ; Monash University, Australia; University of Turku, Finland.
    Wong, Bob B. M.
    Monash University, Australia.
    Svensson, P. Andreas
    Monash University, Australia.
    Meyer, Axel
    University of Konstanz, Germany.
    Adjustment of brood care behaviour in the absence of a mate in two species of Nicaraguan crater lake cichlids2011In: Behavioral Ecology and Sociobiology, ISSN 0340-5443, E-ISSN 1432-0762, Vol. 65, no 4, p. 613-619Article in journal (Refereed)
    Abstract [en]

    In many taxa, parental strategies can vary among individuals. This is especially true in species with biparental care, with males, more often than females, deserting their mates. While there is an abundance of theoretical predictions and empirical data on factors inducing mate abandonment by males, much less is known about what consequences this may have on female behaviour, particularly in the field and in non-avian systems. Here, we compared brood defence rate, behavioural defence types, and brood success of solitary and paired females in two species of Neotropical cichlid fish in their natural habitat. In terms of the rate of territorial aggression towards potential brood predators, solitary females were able to fully compensate in the absence of a male but, in so doing, ended up maintaining smaller territories, which appeared to compromise offspring fitness in at least one of the two species. Hence, our results suggest that even extensive quantitative compensation in parental effort by solitary females may not be enough to ensure adequate qualitative compensation for the lack of male participation, highlighting the importance of distinguishing between these two aspects of compensatory parental care.

  • 329.
    Lekunberri, Itziar
    et al.
    CSIC, Inst Ciencias Mar.
    Gasol, Josep M.
    CSIC, Inst Ciencias Mar.
    Acinas, Silvia G.
    CSIC, Inst Ciencias Mar.
    Gómez-Consarnau, Laura
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. CSIC, Inst Ciencias Mar.
    Crespo, Bibiana G.
    CSIC, Inst Ciencias Mar.
    Casamayor, Emilio O.
    CSIC, Ctr Estud Avancats Blanes.
    Massana, Ramon
    CSIC, Inst Ciencias Mar.
    Pedrós-Alió, Carlos
    CSIC, Inst Ciencias Mar.
    Pinhassi, Jarone
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    The phylogenetic and ecological context of cultured and whole genome-sequenced planktonic bacteria from the coastal NW Mediterranean Sea2014In: Systematic and Applied Microbiology, ISSN 0723-2020, E-ISSN 1618-0984, Vol. 37, no 3, p. 216-228Article in journal (Refereed)
    Abstract [en]

    Microbial isolates are useful models for physiological and ecological studies and can also be used to reassemble genomes from metagenomic analyses. However, the phylogenetic diversity that can be found among cultured marine bacteria may vary significantly depending on the isolation. Therefore, this study describes a set of 136 bacterial isolates obtained by traditional isolation techniques from the Blanes Bay Microbial Observatory, of which seven strains have had the whole genome sequenced. The complete set was compared to a series of environmental sequences obtained by culture-independent techniques (60 DGGE sequences and 303 clone library sequences) previously obtained by molecular methods. In this way, each isolate was placed in both its "ecological" (time of year, nutrient limitation, chlorophyll and temperature values) context or setting, and its "phylogenetic" landscape (i.e. similar organisms that were found by culture-independent techniques, when they were relevant, and when they appeared). Nearly all isolates belonged to the Gammaproteobacteria, Alphaproteobacteria, or the Bacteroidetes (70, 40 and 20 isolates, respectively). Rarefaction analyses showed similar diversity patterns for sequences from isolates and molecular approaches, except for Alphaproteobacteria where cultivation retrieved a higher diversity per unit effort. Approximately 30% of the environmental clones and isolates formed microdiversity clusters constrained at 99% 16S rRNA gene sequence identity, but the pattern was different in Bacteroidetes (less microdiversity) than in the other main groups. Seventeen cases (12.5%) of nearly complete (98-100%) rRNA sequence identity between isolates and environmental sequences were found: nine in the Alphaproteobacteria, five in the Gammaproteobacteria, and three in the Bacteroidetes, indicating that cultivation could be used to obtain at least some organisms representative of the various taxa detected by molecular methods. Collectively, these results illustrated the largely unexplored potential of culturing on standard media for complementing the study of microbial diversity by culture-independent techniques and for obtaining phylogenetically distinct model organisms from natural seawater.

  • 330.
    Lemdahl, Geoffrey
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Broström, Anna
    Hedenäs, Lars
    Arvidsson, Kristina
    Holmgren, Sofia
    Gaillard, Marie-José
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Möller, Per
    Eemian and Early Weichselian environments in southern Sweden: a multi-proxy study of till-covered organic deposits from the Småland peneplain.2013In: Journal of Quaternary Science, ISSN 0267-8179, E-ISSN 1099-1417, Vol. 28, no 7, p. 705-719Article in journal (Refereed)
    Abstract [en]

    Based on their luminescence and infinite radiocarbon ages, organic deposits beneath till at two sites on the Småland peneplain, southern Sweden (Nybygget and Stora Gäddevik), are concluded to have formed before the Middle Weichselian. Applied palaeoecological methods include analyses of pollen, diatoms, charcoal fragments, macroscopic remains of vascular plants and mosses, and insect remains. Pollen-stratigraphical correlations with previously studied interglacial/interstadial sites in southern Sweden, Denmark and northern Germany suggest that the peat at Nybygget dates from the Brørup interstadial or the final stage of the Eemian interglacial, whereas the lake sediments at Stora Gäddevik probably were emplaced during the middle Eemian. We conclude that the peat was formed in a wetland characterized by both wood swamp and open mire vegetation, and surrounded by semi-open woodlands dominated by pine, birch and hazel. The middle Eemian sequence at the Stora Gäddevik site provides evidence of a moderately nutrient-rich to nutrient-rich lake environment with relatively diverse aquatic vegetation. Regional vegetation, as reconstructed using the REVEALS model, was spruce woodland mixed with pine, alder and birch, but also included more open environments with hazel, oak, grasslands and sedge-dominated wetlands. Water shield (Brasenia schreberi), now extinct in Europe, was identified in the Eemian lake deposits, from both pollen and macroscopic remains.

  • 331.
    Lemdahl, Geoffrey
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Buckland, Philip I.
    Umeå Univ.
    Mortensen, Morten Fischer
    Natl Museum Denmark.
    Lateglacial insect assemblages from the Palaeolithic site Slotseng: New evidence concerning climate and environment in SW Denmark2014In: Quaternary International, ISSN 1040-6182, E-ISSN 1873-4553, Vol. 341, p. 172-183Article in journal (Refereed)
    Abstract [en]

    The Slotseng site represents Paleolithic settlements of the Havelte phase of the Hamburgian culture (c. 15 to 14 cal ka BP). The Lateglacial sediment stratigraphy of an adjacent kettle hole was studied in a multidisciplinary project, including the analysis of pollen, macroscopic plant remains, vertebrate bones, and insect remains. In this article the results from the insect analysis are presented. Twelve samples were analysed from a monolith, which chronologically spans from ca. 15,500 to 13,600 cal BP. 108 taxa of Coleoptera and 15 taxa of Trichoptera, Hemiptera, Megaloptera, Diptera and Hymenoptera were recorded. The beetle assemblages indicate an open heath environment with shrub and herb vegetation during this period, with only minor changes during the stadials and interstadials. This is in good agreement with the interpretations based on pollen and plant macrofossil analyses. The presence of dung beetles indicates that reindeer herds grazed in the vicinity of the site. A number of finds of the carrion beetle Thanatophilus dispar suggest that fish may have been a complementary food resource for the hunters at Slotseng. MCR reconstructions indicate arctic/subarctic climate conditions during the periods GS-2a (Pre-Bolling) and GI-1d (Older Dryas) with mean summer temperatures similar to 9-13 degrees C and mean winter temperatures similar to-3 to -20 degrees C. During the interstadials GI-1e (Bolling) and GI-1c (Allerod 1) mean summer temperatures were similar to 14-16 degrees C, but mean winter temperatures remained similar to those during the colder periods. The reconstructed environments and living conditions for the Paleolithic hunters show striking similarities with contemporaneous conditions reconstructed for Magdalenian/Azilian sites at Lake Neuchatel, Switzerland. (C) 2014 Elsevier Ltd and INQUA. All rights reserved.

  • 332.
    Li, Lingni
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Effects of dissolved organic matter and temperature on the bacterial community during spring2016Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Marine bacteria are the main driver in marine ecosystem and the microbial loop in the seawater has been a hot topic in marine science in last decades. Since, there have been some long time-scale monitoring studies about bacterial dynamics in temperate water. Studies about interactions among marine bacteria, dissolved organic matter (DOM) and seawater temperature are still rare. In order to understand more details, a two-factor experiment (DOM added or not, and at 4 °C or 8 °C) was settled after a phytoplankton mesocosm, including the measurements of bacterial abundance (BA), extracellular enzyme activities (EEA) and bacterial activities (including bacterial production (BP), respiration (BR) and growth efficiency (BGE)), as well as 16S rRNA gene sequencing. The water samples for mesocosm were from the harbor near to Kocken, Linnaeus University, Kalmar, south of Sweden. The inoculum of phytoplankton and bacteria, and the water samples for bacteria cultures were from the LMO station. The result of the experiment showed that during experiment period, the most abundant bacteria were Gammaproteobacteria, and Alphaproteobacteria, Bacteroidetes and Betaproteobacteria were secondly abundant. There were significant differences in enzyme activities; BP showed significant differences only in the treatment with adding DOM; no difference in BR was found in 3 µm pore-size filter but it was found significantly different in treatment LD compared to treatments without DOM added in 0.2 µm pore-size filter. Treatment LD (4 °C and DOM added) had statistically significant differences in BGE compared to other treatments. The conclusion was that the change of temperature and DOM concentration resulted in a change of both bacterial growth and community composition. The bacteria were more abundant after adding fresh DOM than those without extra DOM, and at lower temperature, it took longer time for BA to reach to the same abundances in the exponential phase. When the DOM concentration was high, temperature had synergistic effects on the bacterial community. In contrast, when the DOM concentration was low, the influence of temperature was not significant. The bacterial community composition only changed when both temperature DOM concentration were higher. Otherwise, either temperature or DOM concentration was not significant effect on the composition of bacterial community. This studies indicated more information about the bacterial dynamics in the south Baltic Sea in spring according to the seasonal change. Further studies can be focused on a longer-period experiment on bacterial community so that we can get a seasonal blue print of the marine bacteria community dynamic change in the Baltic Sea.

  • 333.
    Lim, S. M.
    et al.
    Artemis One Hlth Res Fdn, Netherlands.
    Geervliet, M.
    Artemis One Hlth Res Fdn, Netherlands;Wageningen Univ, Netherlands.
    Verhagen, Josanne H.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Erasmus MC, Netherlands.
    Muskens, G. J. D. M.
    Wageningen Environm Res Alterra, Netherlands.
    Majoor, F. A.
    Sovon Dutch Ctr Field Ornithol, Netherlands.
    Osterhaus, A. D. M. E.
    Artemis One Hlth Res Fdn, Netherlands;Univ Vet Med Hannover, Germany.
    Martina, B. E. E.
    Artemis One Hlth Res Fdn, Netherlands;Erasmus MC, Netherlands.
    Serologic evidence of West Nile virus and Usutu virus infections in Eurasian coots in the Netherlands2018In: Zoonoses and Public Health, ISSN 1863-1959, E-ISSN 1863-2378, Vol. 65, no 1, p. 96-102Article in journal (Refereed)
    Abstract [en]

    West Nile virus (WNV) and Usutu virus (USUV) are arboviruses that are maintained in enzootic transmission cycles between mosquitoes and birds and are occasionally transmitted to mammals. As arboviruses are currently expanding their geographic range and emerging in often unpredictable locations, surveillance is considered an important element of preparedness. To determine whether sera collected from resident and migratory birds in the Netherlands as part of avian influenza surveillance would also represent an effective source for proactive arbovirus surveillance, a random selection of such sera was screened for WNV antibodies using a commercial ELISA. In addition, sera of jackdaws and carrion crows captured for previous experimental infection studies were added to the selection. Of the 265 screened serum samples, 27 were found to be WNV-antibody-positive, and subsequent cross-neutralization experiments using WNV and USUV confirmed that five serum samples were positive for only WNV-neutralizing antibodies and seven for only USUV. The positive birds consisted of four Eurasian coots (Fulica atra) and one carrion crow (Corvus corone) for WNV, of which the latter may suggest local presence of the virus, and only Eurasian coots for USUV. As a result, the screening of a small selection of serum samples originally collected for avian influenza surveillance demonstrated a seroprevalence of 1.6% for WNV and 2.8% for USUV, suggesting that this sustained infrastructure could serve as a useful source for future surveillance of arboviruses such as WNV and USUV in the Netherlands.

  • 334.
    Lindehoff, Elin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    ALGOLAND – industry and ecology together working to reduce the impact of climate change and eutrophication2015Conference paper (Other academic)
  • 335.
    Lindehoff, Elin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    ALGOLAND: Industry and Ecology Together2018Conference paper (Other (popular science, discussion, etc.))
  • 336.
    Lindehoff, Elin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Algoland kick-off: alger och musslor- klimat och övergödningssänkor med stor potential2016In: Presented at the Algoland Kick-off Conference 2016, Kalmar, Sweden, September 9, 2016, 2016Conference paper (Other academic)
  • 337.
    Lindehoff, Elin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    ALGOLAND återvinner näring och CO2 från industriutsläpp för att producera en värdefull produkt, mikroalger2018Conference paper (Other (popular science, discussion, etc.))
  • 338.
    Lindehoff, Elin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Biologi och Miljövetenskap2018Conference paper (Other (popular science, discussion, etc.))
  • 339.
    Lindehoff, Elin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Mikroalgers potential inom biofiltering av industriell rökgas och processvatten2014Conference paper (Other (popular science, discussion, etc.))
  • 340.
    Lindehoff, Elin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Östersjön - ett hav av möjligheter2014Conference paper (Other (popular science, discussion, etc.))
  • 341.
    Lindehoff, Elin
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Granéli, Edna
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Glibert, Patricia M.
    Influence of Prey and Nutritional Status on the Rate of Nitrogen Uptake by Prymnesium parvum (haptophyte)2010In: Journal of the American Water Resources Association, ISSN 1093-474X, E-ISSN 1752-1688, Vol. 46, p. 121-132Article in journal (Refereed)
  • 342.
    Lindehoff, Elin
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Granéli, Edna
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Glibert, Patricia M
    University of Maryland, Horn Point Laboratory, Cambridge, USA.
    Nitrogen uptake kinetics of Prymnesium parvum (Haptophyte)2011In: Harmful Algae, ISSN 1568-9883, E-ISSN 1878-1470, Vol. 12, p. 70-76Article in journal (Refereed)
    Abstract [en]

    The uptake rates of different nitrogen (N) forms (NO3-, urea, and the amino acids glycine and glutamicacid) by N-deficient, laboratory-grown cells of the mixotrophic haptophyte, Prymnesium parvum, weremeasured and the preference by the cells for the different forms determined. Cellular N uptake rates(rcell, fmol N cell-1 h-1) were measured using 15N-labeled N substrates. P. parvum showed highpreference for the tested amino acids, in particular glutamic acid, over urea and NO3 under the culturenutrient conditions. However, extrapolating these rates to Baltic Seawater summer conditions, P. parvumwould be expected to show higher uptake rates of NO3- and the amino acids relative to urea because ofthe difference in average concentrations of these substrates. A high uptake rate of glutamic acid at lowsubstrate concentrations suggests that this substrate is likely used through extracellular enzymes.Nitrate, urea and glycine, on the other hand, showed a non-saturating uptake over the tested substrateconcentration (1–40 mM-N for NO3- and urea, 0.5–10 mM-N for glycine), indicating slower membranetransportrates for these substrates

  • 343.
    Lindehoff, Elin
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Granéli, Edna
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Graneli, Wilhelm
    Effect of tertiary sewage effluent additions on Prymnesium parvum cell toxicity and stable isotope ratios2009In: Harmful Algae, ISSN 1568-9883, E-ISSN 1878-1470, Vol. 8, no 2, p. 247-253Article in journal (Refereed)
    Abstract [en]

    We investigated the ability of the ichthyotoxic haptophyte Prymnesium parvum to use sewage-originated nutrients applying stable carbon (C) and nitrogen (N) isotope techniques. P. parvum was cultured under N and phosphorus (P) sufficient and deficient conditions in either sewage effluent-based medium or in a nitrate- and phosphate-based control. Cell densities and toxicities were monitored and stable carbon N isotopes signatures (delta(13)C and delta(15)N) of P. parvum and the sewage effluent analysed. Nitrogen and P sufficient cultures achieved the highest biomass followed by P and N deficient cultures, regardless of sewage effluent additions. The P deficient cultures with sewage effluent had higher toxicity, estimated as haemolytic activity (9.4 +/- 0 x 10(-5) mg Saponin equiv. cell(-1)) compared to the P deficient control and to all N deficient and NP sufficient cultures. Nutrient deficient conditions had no effect on the cell delta(15)N, but a decreasing effect on delta(13)C in the inorganic N deficient treatment. Growth in sewage-based media was followed by a substantial increase in the cell delta(15)N (10.4-16.1 parts per thousand) compared to the control treatments (2.4-4.9 parts per thousand), showing that P. parvum is capable of direct use of sewage-originated N, inorganic as well as organic. Uptake of terrestrial derived C in the sewage treatments was confirmed by a decrease in cell delta(13)C, implying that P. parvum is able to utilize organic nutrients in sewage effluent.

  • 344.
    Lindehoff, Elin
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Finnish Environm Inst, Finland.
    Jerney, J.
    Finnish Environm Inst, Finland.
    Le Tortorec, A.
    Finnish Environm Inst, Finland.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Savela, H.
    Univ Turku, Finland.
    Svahn, E.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Suikkanen, S.
    Finnish Environm Inst, Finland.
    Kremp, A.
    Finnish Environm Inst, Finland.
    Nitrogen Supply Mechanisms in Toxic Dinoflagellate Alexandrium ostenfeldii - the Key to Bloom Expansion in Coastal Baltic Waters?2017In: Phycologia, ISSN 0031-8884, E-ISSN 2330-2968, Vol. 56, no 4, p. 118-119Article in journal (Other academic)
  • 345.
    Lindehoff, Elin
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Briggen Tre Kronor: Algoland2014Conference paper (Other (popular science, discussion, etc.))
  • 346.
    Lindehoff, Elin
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Olofsson, Martin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    ALGOLAND – Recovery: avfall används för att producera en värdefull produkt - algbiomassa2018In: Presented at the Algoland 2030 Workshop, Kalmar, Sweden, April 24, 2018, 2018Conference paper (Other academic)
  • 347.
    Lindh, Markus V.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Bacterioplankton population dynamics in a changing ocean2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Bacterioplankton is characterized by high diversity, short generation times and rapid turnover. Despite their small size, these numerous microorganisms are a fundamental piece of aquatic ecosystems by channeling carbon to higher trophic levels through dissolved organic matter utilization. Yet, several gaps remain in our knowledge and understanding of bacterioplankton populations regarding detailed temporal dynamics, and mechanisms determining biogeographical patterns and potential responses to climate change. The aim of this thesis was to examine responses in bacterioplankton community composition and function when challenged by natural and anthropogenically-induced change in environmental conditions.

    High temporal resolution analysis of bacterioplankton population dynamics in the Baltic Sea indicated detailed seasonal responses. It also showed a similar but wide spectrum of niche differentiation patterns within several major bacterial groups. Analysis of geographic distributions of marine bacterial populations revealed bimodal occupancy-frequency patterns in bacterial communities, indicating that the presence of many locally rare taxa along with a few locally abundant taxa were explained by stochastic variation in colonization and extinction rates. Experimental manipulations with natural marine bacterioplankton assemblages revealed both specialist and generalist strategies in utilizing specific dissolved organic carbon compounds. When subjected to experimentally increased sea surface temperatures, lowered pH and additions of terrigenous carbon, some populations decreased in relative abundance while others were stable; concomitantly, many populations increased in relative abundance. Shifts in bacterial community composition were shown to correlate with changes in community functioning, but detection of such correlations depended largely on the detail of phylogenetic analysis and successional stage of the communities.

    The results in this thesis suggest that both natural and anthropogenically-induced changes in environmental conditions promote simultaneous adjustment and replacement of bacterial populations tightly linked with metabolic plasticity. These trade-offs play a significant role for understanding the relationship between bacterioplankton population dynamics and potential shifts in carbon cycling properties. We also show the importance of regional effects in shaping bacterial community composition, crucial for interpreting bacterioplankton distribution patterns. In conclusion, this thesis emphasizes the critical importance of connecting analysis of bacterioplankton population dynamics with examination of ecological mechanisms to improve our understanding of factors that regulate the distribution and activity of distinct bacterioplankton populations.

  • 348.
    Lindh, Markus V.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Figueroa, Daniela
    Umeå University.
    Sjöstedt, Johanna
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Baltar, Federico
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. University of Otago, New Zealand.
    Lundin, Daniel
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Andersson, Agneta
    Umeå University.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Pinhassi, Jarone
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Transplant experiments uncover Baltic Sea basin-specific responses in bacterioplankton community composition and metabolic activities2015In: Frontiers in Microbiology, ISSN 1664-302X, E-ISSN 1664-302X, Vol. 6, article id 223Article in journal (Refereed)
    Abstract [en]

    Anthropogenically induced changes in precipitation are projected to generate increased river runoff to semi-enclosed seas, increasing loads of terrestrial dissolved organic matter and decreasing salinity. To determine how bacterial community structure and functioning adjust to such changes, we designed microcosm transplant experiments with Baltic Proper (salinity 7.2) and Bothnian Sea (salinity 3.6) water. Baltic Proper bacteria generally reached higher abundances than Bothnian Sea bacteria in both Baltic Proper and Bothnian Sea water, indicating higher adaptability. Moreover, Baltic Proper bacteria growing in Bothnian Sea water consistently showed highest bacterial production and beta-glucosidase activity. These metabolic responses were accompanied by basin-specific changes in bacterial community structure. For example, Baltic Proper Pseudomonas and Limnobacter populations increased markedly in relative abundance in Bothnian Sea water, indicating a replacement effect. In contrast, Roseobacter and Rheinheimera populations were stable or increased in abundance when challenged by either of the waters, indicating an adjustment effect. Transplants to Bothnian Sea water triggered the initial emergence of particular Burkholderiaceae populations, and transplants to Baltic Proper water triggered Alteromonadaceae populations. Notably, in the subsequent re-transplant experiment, a priming effect resulted in further increases to dominance of these populations. Correlated changes in community composition and metabolic activity were observed only in the transplant experiment and only at relatively high phylogenetic resolution. This suggested an importance of successional progression for interpreting relationships between bacterial community composition and functioning. We infer that priming effects on bacterial community structure by natural episodic events or climate change induced forcing could translate into long-term changes in bacterial ecosystem process rates.

  • 349.
    Lindh, Markus V.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Lefebure, Robert
    Marine Stewardship Council, UK.
    Degerman, Rickard
    Umeå Univ.
    Lundin, Daniel
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Andersson, Agneta
    Umeå Univ.
    Pinhassi, Jarone
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Consequences of increased terrestrial dissolved organic matter and temperature on bacterioplankton community composition during a Baltic Sea mesocosm experiment2015In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 44, no Supplement 3, p. S402-S412Article in journal (Refereed)
    Abstract [en]

    Predicted increases in runoff of terrestrial dissolved organic matter (DOM) and sea surface temperatures implicate substantial changes in energy fluxes of coastal marine ecosystems. Despite marine bacteria being critical drivers of marine carbon cycling, knowledge of compositional responses within bacterioplankton communities to such disturbances is strongly limited. Using 16S rRNA gene pyrosequencing, we examined bacterioplankton population dynamics in Baltic Sea mesocosms with treatments combining terrestrial DOM enrichment and increased temperature. Among the 200 most abundant taxa, 62 % either increased or decreased in relative abundance under changed environmental conditions. For example, SAR11 and SAR86 populations proliferated in combined increased terrestrial DOM/temperature mesocosms, while the hgcI and CL500-29 clades (Actinobacteria) decreased in the same mesocosms. Bacteroidetes increased in both control mesocosms and in the combined increased terrestrial DOM/temperature mesocosms. These results indicate considerable and differential responses among distinct bacterial populations to combined climate change effects, emphasizing the potential of such effects to induce shifts in ecosystem function and carbon cycling in the future Baltic Sea.

  • 350.
    Lindh, Markus V.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Riemann, Lasse
    Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark.
    Baltar, Federico
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Romero-Oliva, Claudia
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Salomon, Paulo
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Granéli, Edna
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Pinhassi, Jarone
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Consequences of increased temperature and acidification on bacterioplankton community composition during a mesocosm spring bloom in the Baltic Sea2013In: Environmental Microbiology Reports, ISSN 1758-2229, E-ISSN 1758-2229, Vol. 5, no 2, p. 252-262Article in journal (Refereed)
    Abstract [en]

    Despite the paramount importance of bacteria for biogeochemical cycling of carbon and nutrients, little is known about the potential effects of climate change on these key organisms. The consequences of the projected climate change on bacterioplankton community dynamics were investigated in a Baltic Sea spring phytoplankton bloom mesocosm experiment by increasing temperature with 3°C and decreasing pH by approximately 0.4 units via CO2 addition in a factorial design. Temperature was the major driver of differences in community composition during the experiment, as shown by denaturing gradient gel electrophoresis (DGGE) of amplified 16S rRNA gene fragments. Several bacterial phylotypes belonging to Betaproteobacteria were predominant at 3°C but were replaced by members of the Bacteriodetes in the 6°C mesocosms. Acidification alone had a limited impact on phylogenetic composition, but when combined with increased temperature, resulted in the proliferation of specific microbial phylotypes. Our results suggest that although temperature is an important driver in structuring bacterioplankton composition, evaluation of the combined effects of temperature and acidification is necessary to fully understand consequences of climate change for marine bacterioplankton, their implications for future spring bloom dynamics, and their role in ecosystem functioning.

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