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  • 251.
    Johansson, Karin S. L.
    et al.
    Swedish University of Agricultural Sciences.
    Vrede, Tobias
    Swedish University of Agricultural Sciences.
    Lebret, Karen
    Lund University.
    Johnson, Richard K.
    Swedish University of Agricultural Sciences.
    Zooplankton Feeding on the Nuisance Flagellate Gonyostomum semen2013In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 8, no 5, p. e62557-Article in journal (Refereed)
    Abstract [en]

    The large bloom-forming flagellate Gonyostomum semen has been hypothesized to be inedible to naturally occurring zooplankton due to its large cell size and ejection of long slimy threads (trichocysts) induced by physical stimulation. In a grazing experiment using radiolabelled algae and zooplankton collected from lakes with recurring blooms of G. semen and lakes that rarely experience blooms, we found that Eudiaptomus gracilis and Holopedium gibberum fed on G. semen at high rates, whereas Daphnia cristata and Ceriodaphnia spp. did not. Grazing rates of E. gracilis were similar between bloom-lakes and lakes with low biomass of G. semen, indicating that the ability to feed on G. semen was not a result of local adaptation. The high grazing rates of two of the taxa in our experiment imply that some of the nutrients and energy taken up by G. semen can be transferred directly to higher trophic levels, although the predominance of small cladocerans during blooms may limit the importance of G. semen as a food resource. Based on grazing rates and previous observations on abundances of E. gracilis and H. gibberum, we conclude that there is a potential for grazer control of G. semen and discuss why blooms of G. semen still occur.

  • 252. Johansson, N
    et al.
    Granéli, Edna
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Toxicity of Chrysochromulina polylepis cells growing in different N:P ratios1998In: Harmful algae = Algas nocivas: proceedings of the VIII International Conference on Harmful Algae, Vigo, Spain, 25-29 June 1997 / [ed] Reguera B, Blanco J, Fernandez LM & Wyatt T, Xunta de Galicia and IOC-UNESCO , 1998, p. 329-330Chapter in book (Other academic)
  • 253.
    Johansson, Victor
    et al.
    Swedish University of Agricultural Science.
    Knape, Jonas
    Swedish University of Agricultural Science.
    Franzén, Markus
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Helmholtz-Centre for Environmental Research - UfZ, Germany.
    Population dynamics and future persistence of the clouded Apollo butterfly in southern Scandinavia: The importance of low intensity grazing and creation of habitat patches2017In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 206, p. 120-131Article in journal (Refereed)
    Abstract [en]

    We investigated the population dynamics and future persistence of the last remaining Clouded Apollo butterfly metapopulation in southern Scandinavia. Based on three decades of surveys (1984-2015), we modelled colonization-extinction dynamics and local population sizes using habitat patch characteristics and connectivity, while accounting for imperfect detection and uncertainty in the local population sizes. The colonization probability increased with increasing connectivity and the local extinction probability decreased with increasing local population size in accordance with metapopulation theory. The local population size increased with increasing patch area, and was also affected by grazing intensity. Light grazing resulted in larger local populations compared to heavy grazing or no grazing at all. The butterfly population has decreased considerably during the study period and according to projections of future dynamics the estimated extinction risk within the coming 10 years is 17%. However, it is possible to change the negative trends and decrease the extinction risk considerably by conservation actions. By optimizing the grazing pressure in existing patches the extinction risk was reduced to 11% (a reduction with 35% compared to the scenario with no conservation action). If a few new patches are created close to the occupied ones the extinction risk can be reduced further. In conclusion, there is a large risk that the Clouded Apollo butterfly will go extinct from southern Scandinavia within the coming decade. However, conservation measures that are focused to the core area of the current distribution and applied soon can considerably improve the situation for the butterfly. (C) 2016 Elsevier Ltd. All rights reserved.

  • 254.
    Jourdain, Elsa
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Olsen, Björn
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Lundkvist, Ake
    Hubálek, Zdenek
    Sikutová, Silvie
    Waldenström, Jonas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Karlsson, Malin
    Wahlström, Maria
    Jozan, Martine
    Falk, Kerstin I
    Surveillance for West Nile virus in wild birds from northern Europe.2011In: Vector Borne and Zoonotic Diseases, ISSN 1530-3667, E-ISSN 1557-7759, Vol. 11, no 1, p. 77-79Article in journal (Refereed)
    Abstract [en]

    A total of 1935 migratory birds from 104 different species were captured in southeastern Sweden in 2005-2006 and tested for antibodies against West Nile virus (WNV). Overall, 46 birds (2.4%; binomial confidence limits, 1.8-3.2) were positive by blocking-ELISA, but only 2 (0.10%; binomial confidence limits, 0.0-0.4) had antibodies detectable by both blocking-ELISA and WNV neutralization test. ELISA-positive birds included long- and short-distance migrants likely exposed to WNV while wintering in or migrating through areas enzootic for WNV. Exposure to a cross-reactive Flavivirus was suspected for short-distance migrants of the Turdidae family, but no cross-neutralization with tick-borne encephalitis and Usutu viruses was observed.

  • 255.
    Jourdain, Elsa
    et al.
    INRA, France.
    van Riel, Debby
    Erasmus Medical Center, The Netherlands.
    Munster, Vincent J
    National Institutes of Health, USA.
    Kuiken, Thijs
    Erasmus Medical Center, The Netherlands.
    Waldenström, Jonas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Olsen, Björn
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences. Uppsala University.
    Ellström, Patrik
    Uppsala University.
    The pattern of influenza virus attachment varies among wild bird species2011In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 6, no 9, article id e24155Article in journal (Refereed)
    Abstract [en]

    The ability to attach to host cells is one of the main determinants of the host range of influenza A viruses. By using virus histochemistry, we investigate the pattern of virus attachment of both a human and an avian influenza virus in colon and trachea sections from 12 wild bird species. We show that significant variations exist, even between closely related avian species, which suggests that the ability of wild birds to serve as hosts for influenza viruses strongly varies among species. These results will prove valuable to assess the possibilities of interspecies transmission of influenza viruses in natural environments and better understand the ecology of influenza.

  • 256.
    Järhult, Josef D.
    et al.
    Uppsala University.
    Muradrasoli, Shaman
    Swedish University of Agricultural Sciences.
    Wahlgren, John
    Swedish Institute for Infectious Disease Control ; Karolinska Institutet.
    Söderström, Hanna
    Umeå University.
    Orozovic, Goran
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Gunnarsson, Gunnar
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences. Kristianstad University.
    Bröjer, Caroline
    National Veterinary Institute ; Swedish University of Agricultural Sciences.
    Latorre-Margalef, Neus
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Fick, Jerker
    Umeå University.
    Grabic, Roman
    Umeå University ; University of South Bohemia in Ceske Budejovice, Czech Republic.
    Lennerstrand, Johan
    Uppsala University.
    Waldenström, Jonas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Lundkvist, Ake
    Swedish Institute for Infectious Disease Control ; Karolinska Institutet.
    Olsen, Björn
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences. Uppsala University.
    Environmental levels of the antiviral oseltamivir induce development of resistance mutation H274Y in influenza A/H1N1 virus in mallards2011In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 6, no 9, article id e24742Article in journal (Refereed)
    Abstract [en]

    Oseltamivir (Tamiflu®) is the most widely used drug against influenza infections and is extensively stockpiled worldwide as part of pandemic preparedness plans. However, resistance is a growing problem and in 2008-2009, seasonal human influenza A/H1N1 virus strains in most parts of the world carried the mutation H274Y in the neuraminidase gene which causes resistance to the drug. The active metabolite of oseltamivir, oseltamivir carboxylate (OC), is poorly degraded in sewage treatment plants and surface water and has been detected in aquatic environments where the natural influenza reservoir, dabbling ducks, can be exposed to the substance. To assess if resistance can develop under these circumstances, we infected mallards with influenza A/H1N1 virus and exposed the birds to 80 ng/L, 1 µg/L and 80 µg/L of OC through their sole water source. By sequencing the neuraminidase gene from fecal samples, we found that H274Y occurred at 1 µg/L of OC and rapidly dominated the viral population at 80 µg/L. IC₅₀ for OC was increased from 2-4 nM in wild-type viruses to 400-700 nM in H274Y mutants as measured by a neuraminidase inhibition assay. This is consistent with the decrease in sensitivity to OC that has been noted among human clinical isolates carrying H274Y. Environmental OC levels have been measured to 58-293 ng/L during seasonal outbreaks and are expected to reach µg/L-levels during pandemics. Thus, resistance could be induced in influenza viruses circulating among wild ducks. As influenza viruses can cross species barriers, oseltamivir resistance could spread to human-adapted strains with pandemic potential disabling oseltamivir, a cornerstone in pandemic preparedness planning. We propose surveillance in wild birds as a measure to understand the resistance situation in nature and to monitor it over time. Strategies to lower environmental levels of OC include improved sewage treatment and, more importantly, a prudent use of antivirals.

  • 257. Jönsson, Ingemar K.
    et al.
    Herczeg, Gabor
    O'Hara, Robert B.
    Söderman, Fredrik
    ter Schure, Arnout F.H.
    Larsson, Per
    Lund Univ, Dept Ecol, SE-22362 Lund.
    Merilä, Juha
    Sexual patterns of prebreeding energy reserves in the common frog Rana temporaria along a latitudinal gradient2009In: Ecography, ISSN 0906-7590, E-ISSN 1600-0587, Vol. 32, no 5, p. 831-839Article in journal (Refereed)
    Abstract [en]

    The ability to store energy is an important life history trait for organisms facing long periods without energy income, and in particular for capital breeders such as temperate zone amphibians, which rely on stored energy during reproduction. However, large scale comparative studies of energy stores in populations with different environmental constraints on energy allocation are scarce. We investigated energy storage patterns in spring (after hibernation and before reproduction) in eight common frog Rana temporaria populations exposed to different environmental conditions along a 1600 km latitudinal gradient across Scandinavia (range of annual activity period is 3-7 months). Analyses of lean body weight (eviscerated body mass), weight of fat bodies, liver weight, and liver fat content, showed that 1) post-hibernation/pre-breeding energy stores increased with increasing latitude in both sexes, 2) males generally had larger energy reserves than females and 3) the difference in energy stores between sexes decreased towards the north. Larger energy reserves towards the north can serve as a buffer against less predictable and/or less benign weather conditions during the short activity period, and may also represent a risk-averse tactic connected with a more pronounced iteroparous life history. In females, the continuous and overlapping vitellogenic activity in the north may also demand more reserves in early spring. The general sexual difference could be a consequence of the fact that, at the time of our sampling, females had already invested their energy into reproduction in the given year (i.e. their eggs were already ovulated), while the males' main reproductive activities (e.g. calling, mate searching, sexual competition) occurred later in the season.

  • 258.
    Kaplan, Jed O.
    et al.
    Max Planck Inst Sci Human Hist, Germany;ARVE Res Sarl, Switzerland.
    Krumhardt, Kristen M.
    Univ Colorado Boulder, USA.
    Gaillard, Marie-José
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Sugita, Shinya
    Tallinn Univ, Estonia.
    Trondman, Anna-Kari
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Fyfe, Ralph
    Univ Plymouth, UK.
    Marquer, Laurent
    Univ Toulouse Jean Jaures, France.
    Mazier, Florence
    Univ Toulouse Jean Jaures, France.
    Nielsen, Anne Birgitte
    Lund University.
    Constraining the Deforestation History of Europe: Evaluation of Historical Land Use Scenarios with Pollen-Based Land Cover Reconstructions2017In: Land, ISSN 2073-445X, E-ISSN 2073-445X, Vol. 6, no 4, article id 91Article in journal (Refereed)
    Abstract [en]

    Anthropogenic land cover change (ALCC) is the most important transformation of the Earth system that occurred in the preindustrial Holocene, with implications for carbon, water and sediment cycles, biodiversity and the provision of ecosystem services and regional and global climate. For example, anthropogenic deforestation in preindustrial Eurasia may have led to feedbacks to the climate system: both biogeophysical, regionally amplifying winter cold and summer warm temperatures, and biogeochemical, stabilizing atmospheric CO2 concentrations and thus influencing global climate. Quantification of these effects is difficult, however, because scenarios of anthropogenic land cover change over the Holocene vary widely, with increasing disagreement back in time. Because land cover change had such widespread ramifications for the Earth system, it is essential to assess current ALCC scenarios in light of observations and provide guidance on which models are most realistic. Here, we perform a systematic evaluation of two widely-used ALCC scenarios (KK10 and HYDE3.1) in northern and part of central Europe using an independent, pollen-based reconstruction of Holocene land cover (REVEALS). Considering that ALCC in Europe primarily resulted in deforestation, we comparemodeled land use with the cover of non-forest vegetation inferred from the pollen data. Though neither land cover change scenario matches the pollen-based reconstructions precisely, KK10 correlates well with REVEALS at the country scale, while HYDE systematically underestimates land use with increasing magnitude with time in the past. Discrepancies between modeled and reconstructed land use are caused by a number of factors, including assumptions of per-capita land use and socio-cultural factors that cannot be predicted on the basis of the characteristics of the physical environment, including dietary preferences, long-distance trade, the location of urban areas and social organization.

  • 259.
    Karpestam, Einat
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Causes and consequences of niche differentiation between color morphs of pygmy grasshoppers2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis, I used the color polymorphic pygmy grasshopper, Tetrix subulata, as a model system in order to investigate the degree of niche differentiation between alternative color morphs that are present within a single population. First, I hypothesized that individuals belonging to different color morphs differ in their innate food preference due to somewhat dissimilar physiology, and in their actual food consumption due in part to differential habitat use. I found that alternative morphs differ in their preferred food (multiple-choice experiment in the lab), and in long-term consumption of food in the wild (stable isotopes analysis). Next, I investigated what kind of ecological constraints may result in differential habitat use? Firstly, by painting grasshoppers either black or white in order to influence their thermal properties, I demonstrated that thermoregulatory behavior results in differential microhabitat use in a way that may increase fitness. Secondly, in computer based experiments in which human ‘predators’ were asked to detect images of grasshoppers implemented in images of various environments, I further demonstrated that the degree to which a specific body coloration supply protection, changes across backgrounds, and that no single color pattern provides superior protection against all visual backgrounds. Thus, predator avoidance behavior may result in differential habitat use as well. Can these findings translate into an advantage of polymorphic relative to monomorphic populations?  I then evaluated one prediction from theory that posits that more variable founder groups will be more successful in establishing population in new environments. Indeed, I found higher number of individuals the following year in more variable founder groups in semi-natural conditions in field experiment. This thesis demonstrates, niche differentiation along several dimensions between alternative color morph in a generalist invertebrate. It provides experimental evidence supporting the notion that visual predation may be driving force behind evolutionary change in morph frequencies, and points to a possible advantage for color polymorphic relative to monomorphic groups in terms of a higher establishment success.

  • 260.
    Karpestam, Einat
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Forsman, Anders
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Dietary differences among colour morphs of pygmy grasshoppers revealed by behavioural experiments and stable isotopes.2011In: Evolutionary Ecology Research, ISSN 1522-0613, E-ISSN 1937-3791, Vol. 13, p. 461-477Article in journal (Refereed)
  • 261.
    Karpestam, Einat
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Wennersten, Lena
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Forsman, Anders
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Matching habitat choice by experimentally mismatched phenotypes2012In: Evolutionary Ecology, ISSN 0269-7653, E-ISSN 1573-8477, Vol. 26, no 4, p. 893-907Article in journal (Refereed)
    Abstract [en]

    Gene flow is often regarded a random process that homogenizes differencesbetween populations and constrains local adaptation. However, the matching habitat choicehypothesis posits that individuals actively choose those microhabitats that best match theirspecific phenotype to maximize fitness. Dispersal (and possibly gene flow) may thus bedirected. Many studies report associations between habitats and phenotypes, but they mayreflect selection, plasticity or adaptation rather than matching choice. Here, we test twopredictions from the matching habitat choice hypothesis by manipulating the dorsal colourof Tetrix subulata, a pygmy grasshopper. (1) Is microhabitat choice flexible such thatdifferently manipulated phenotypes distribute themselves differently in a microclimaticand solar radiation mosaic? (2) If they do, are their fitness prospects higher in the morepreferred microhabitat? We find that individuals painted white or black do distributethemselves differently, with black individuals residing in habitats with less radiation, onaverage, than white individuals, demonstrating that microhabitat choices are plastic. Furthermore,white females had more hatchlings than black ones in the increased radiationtreatment, and this was mainly due to increased mortality of black females under increasedradiation. These findings provide rare experimental evidence in line with predictions fromthe matching habitat choice hypothesis.

  • 262.
    Kleiber, Joseph R.
    et al.
    Oregon State University.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. The New Zealand Institute for Plant & Food Research Ltd., PB 4704, Christchurch, 8140, New Zealand.
    Lee, Jana
    USDAÐARS, Horticulture Crops Research Unit, Corvallis, OR 97331.
    Maxwell Suckling, David
    The New Zealand Institute for Plant & Food Research Ltd., PB 4704, Christchurch, 8140, New Zealand.
    Qian, Michael
    Oregon State University, Food Science and Technology, Corvallis, OR 97331.
    Bruck, Denny J.
    DuPont Pioneer, 7300 NW 62nd Ave., PO Box 1004, Johnston, IA 50131.
    Attractiveness of Fermentation and Related Products to Spotted Wing Drosophila (Diptera: Drosophilidae)2014In: Environmental Entomology, ISSN 0046-225X, E-ISSN 1938-2936, Vol. 43, no 2, p. 439-447Article in journal (Refereed)
    Abstract [en]

    Laboratory screening bioassays and field trapping experiments of spotted wing drosophila flies, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), were conducted to determine the attractiveness of 17 compounds as well as to compare attractant efficiency during peak fruit ripeness and postharvest captures late in the season. Compounds structurally related to each of the fermentation products acetic acid, ethanol, ethyl acetate, and 2-phenethyl alcohol were screened for attractiveness compared with a soap water control in greenhouse cage bioassays. The compounds determined to be attractive in the greenhouse bioassay (methanol, ethanol, propanol, formic acid, acetic acid, ethyl acetate, propyl acetate, phenethyl acetate, phenethyl propionate, and phenethyl butyrate) were individually tested in the field added to apple cider vinegar (ACV). The acids were also tested individually in neutralized AVC (NACV; pH 7). Combinations of the compounds were tested in NACV. The capture numbers in ACV traps were not significantly increased by the addition of any of the compounds tested, although significant deterrent effects of some of the compoundsallowed differences between treatments to be observed. Compounds that are most prevalent in wine and vinegar (methanol, ethanol, acetic acid, and ethyl acetate) as well as phenethyl propionate and phenethyl butyrate were less deterrent than the other compounds tested in the field. Captures during peak fruit ripeness were compared with the postharvest period when fruit hosts were not available or were overripe. Although the total number of flies captured late in the season was lower, the trends in treatment performance were similar, indicating a consistent performance of these baits from peak fruit ripeness through postharvest.

  • 263. Krogh, P
    et al.
    Edler, L.
    Granéli, Edna
    Lunds universitet.
    Nyman, U
    Outbreak of diarrheic shellfish poisoning on the west coast of Sweden1985In: Toxic dinoflagellates: proceedings of the Third International Conference on Toxic Dinoflagellates, St. Andrews, New Brunswick, Canada, June 8-12, 1985 / [ed] Donald Mark Anderson, Alan W. White, Daniel G. Baden, New York: Elsevier, 1985, p. 501-503Chapter in book (Other academic)
  • 264.
    Larsson, Folke K
    et al.
    Uppsala University, Sweden.
    Larsson, Kjell
    Uppsala University, Sweden.
    Body size and nesting behaviour of the sand wasp Stictia heros (Hymenoptera: Sphecidae) in Costa Rica1989In: Journal of Tropical Ecology, ISSN 0266-4674, E-ISSN 1469-7831, Vol. 5, no 1, p. 117-120Article in journal (Refereed)
  • 265.
    Larsson, Kjell
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Ejder och alfågel: kan vi vända en nedåtgående trend2015In: Svealands kustvattenförbund, , p. 3p. 29-36Article in journal (Other academic)
  • 266.
    Larsson, Kjell
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Sjöfart och naturvärden vid utsjöbankar i centrala Östersjön2016Report (Other academic)
    Abstract [sv]

    Rapporten beskriver effekter av sjöfart på naturvärden i havsområdet vid de tre stora utsjöbankarna Hoburgs bank, Norra Midsjöbanken och Södra Midsjöbanken. I rapporten diskuteras hur konflikter mellan sjöfart och naturvärden kan reduceras, bland annat genom ändring av fartygsrutter.

  • 267.
    Larsson, Kjell
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Sjöfartens miljöpåverkan kan minskas2016In: Havsutsikt, ISSN 1104-0513, no 2, p. 19-21Article in journal (Other academic)
  • 268.
    Larsson, Kjell
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Sjöfåglars utnyttjande av havsområden runt Gotland och Öland: betydelsen av marint områdesskydd2018Report (Other academic)
    Abstract [sv]

    Marint områdesskydd, dvs. att införa särskilda bevarandeåtgärder i geografiskt definierade marina områden, är ett av flera verktyg som kan användas för att bevara hotade och sårbara populationer av sjöfåglar och annan marin fauna och flora. Havs- och kustområdena runt Gotland och Öland, inklusive de tre större utsjöbankarna i centrala Östersjön, är viktiga områden där sjöfåglar söker föda i form av bottenfauna, främst musslor, eller fisk. Flera fiskätande och bottenfaunaätande sjöfåglar befinner sig vintertid ofta i det yttre kustbandet eller långt ute till havs. Alkor, lommar och havslevande dykänder är mycket skickliga dykare och fångar föda på stora djup. Alfåglar dyker regelbundet efter musslor på djup ned till 25 meter. Alkor som sillgrissla och tordmule dyker efter fisk i den fria vattenmassan och kan fånga byten på betydligt större djup.

     

    Syftet med denna rapport är att sammanställa och tolka tidigare genomförda inventeringar av sjöfåglar i Östersjön, med särskilt fokus på fåglarnas utbredning och nyttjande av utsjöbankar och havs- och kustområden runt Gotland och Öland. Syftet är också att diskutera om och hur marint områdesskydd, havsplanering och andra generella skyddsåtgärder kan påverka olika arter sjöfåglar och särskilt de arter eller populationer som är hotade eller som Sverige har ett särskilt ansvar för.

     

    I rapporten beskrivs hur sjöfågelinventeringar till havs kan genomföras och hur resultat från inventeringar som använt olika metodik bör tolkas. Därefter följer en generell beskrivning av de bottenfaunaätande och fiskätande sjöfågelarter som regelmässigt utnyttjar havsområden runt Gotland och Öland under en betydande tid av året. I denna del beskrivs även artens status och olika hot. Sjöfågelarter eller andra kustbundna fågelarter som i huvudsak endast utnyttjar de mest strandnära vattenområdena tas inte upp i denna rapport. Efter artbeskrivningarna följer en beskrivning av förekomsten av olika arter sjöfåglar i utvalda fokusområden. Avslutningsvis diskuteras behov och prioriteringar av marint områdesskydd i de olika fokusområdena respektive behov av generella skyddsåtgärder

     

    Rapporten har producerats inom projektet ”Marina skyddsvärden runt Gotland och Öland ” som letts av Länsstyrelsen i Gotlands län. Projektet har till största del finansierats av Havs- och vattenmyndigheten genom anslag 1:11 Åtgärder i havs- och vattenmiljö samt medfinansierats av Länsstyrelsen i Gotlands län, Länsstyrelsen i Kalmar län och Linnéuniversitetet.

  • 269.
    Larsson, Kjell
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    The Baltic Sea is an important wintering area for waterbirds2017In: Biological Oceanography of the Baltic Sea / [ed] Snoeijs-Leijonmalm, P., Schubert, H. and Radziejewska, T. (Eds.), Springer Science+Business Media B.V., 2017, p. 438-439Chapter in book (Refereed)
  • 270.
    Larsson, Kjell
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    The common eider, the great cormorant and the white-tailed eagle2017In: Biological Oceanography of the Baltic Sea / [ed] Snoeijs-Leijonmalm, P., Schubert, H. and Radziejewska, T., Springer Science+Business Media B.V., 2017, p. 164-166Chapter in book (Refereed)
  • 271.
    Larsson, Kjell
    et al.
    Uppsala University, Sweden.
    Forslund, Pär
    Uppsala University, Sweden.
    Population dynamics of the barnacle goose Branta leucopsis in the Baltic area: density-dependent effects on reproduction1994In: Journal of Animal Ecology, ISSN 0021-8790, E-ISSN 1365-2656, Vol. 63, no 4, p. 954-962Article in journal (Refereed)
    Abstract [en]

    1. The three largest breeding colonies of barnacle geese Branta leucopsis in the Baltic area were studied from their natural establishments in 1971, 1982 and 1987, respectively, to 1993. The number of breeding pairs increased from one pair in 1971 to 1550, 225 and 150 pairs in the largest, second largest, and third largest colonies, respectively, in 1993. 2. Data on clutch size and number of hatched and fledged young were collected from the beginning or the middle of the 1980s. In the largest colony most data on reproductive success were obtained from observations of individually marked geese. 3. Mean clutch size differed among years and colonies. However, there was no trend for decreasing mean clutch size with increasing density in any of the colonies. Hatching success did not decrease with increasing density in the largest colony. 4. The production of fledged young per breeding pair declined drastically in the largest colony as numbers of breeding pairs rose. This decline was mainly caused by an increasing proportion of the breeding pairs failing to produce any fledged young at all. 5. The relative contribution of the smaller colonies to the total production of fledged young in the Baltic area increased considerably over the study years. In 1993, colony 2 hosted only about 13% of the number of breeding pairs in colonies 1 and 2 combined, but it produced about 38% of the fledged young. 6. Our results point out the need to study populations of colonially nesting geese on a colony by colony basis in order to detect density-dependent effects on reproduction.

  • 272.
    Larsson, Kjell
    et al.
    Uppsala University, Sweden.
    Forslund, Pär
    Uppsala University, Sweden.
    Gustafsson, Lars
    Uppsala University, Sweden.
    Ebbinge, Barwolt S
    Rijksinstituut voor natuurbeheer, The Netherlands.
    From the High Arctic to the Baltic: The successful establishment of a Barnacle Goose Branta leucopsis population on Gotland, Sweden1988In: Ornis Scandinavica, ISSN 0908-8857, Vol. 19, no 3, p. 182-189Article in journal (Refereed)
    Abstract [en]

    Fecundity, survival, immigration and emigration in a recently established population of Barnacle Goose on Gotland, Sweden, are analysed using data from 1971 to 1985. During this period numbers increased from one to 450 breeding pairs. A simulation of population growth using a deterministic population growth model showed that immigration must have occurred during this period, probably mainly during the late 1970s and early 1980s. This net influx together with a high and stable reproductive success and a high annual survival rate resulted in exponential increase in numbers. Several fecundity parameters were higher in the Gotland population than in the Arctic populations of Barnacle Goose. This successful establishment in a temperate area more than 1,300 km south of and 2,000 km away form the species' usual breeding range, questions many explanations of Arctic distributions in geese, for example the hypothesis that a too low protein content in the food plants prevents breeding at lower latitudes.

  • 273.
    Larsson, Kjell
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Hajdu, Susanna
    Stockholm Univ.
    Kilpi, Mikael
    Åbo Akad Univ.
    Larsson, Rolf
    Utklippan Bird Stn.
    Leito, Aivar
    Estonian Univ Life Sci.
    Lyngs, Peter
    Christianso Fieldstn.
    Effects of an extensive Prymnesium polylepis bloom on breeding eiders in the Baltic Sea2014In: Journal of Sea Research, ISSN 1385-1101, E-ISSN 1873-1414, Vol. 88, p. 21-28Article in journal (Refereed)
    Abstract [en]

    The effects of an extensive bloom of the potentially toxic Prymnesium polylepis (Haptophyta) on breeding eiders (Somateria mollissima) in the Baltic Sea were analysed. Increasing abundances of the alternate stage P. polylepis was detected by a marine monitoring programme in the autumn 2007. The bloom peaked between March and May 2008 in the southern, central and northwestern Baltic Proper and abundances of up to 5 x 106 cells l- 1 were recorded. At several sites P. polylepis constituted between 30 and 90% of the total phytoplankton biovolume. The flagellate was only recorded in low numbers in the northeastern Baltic Proper and Gulf of Finland. The abundances were low in 2007, 2009 and 2010. In 28 eider colonies situated in the southern and central Baltic Proper, sharp and synchronous declines in the number of nesting eiders were observed from 2007 to 2008. In colonies on Gotland in the central Baltic Proper, a 76% decrease, from 6650 nests to 1620 nests, was followed by increases in 2009 and 2010, although not up to numbers observed in 2007. At Utklippan and Ertholmene in the southern Baltic Proper, the observed decreases of 55%, from 144 to 65 nests, and 36%, from 1660 to 1060 nests, respectively, between 2007 and 2008, were followed by increases in 2009 and 2010 up to the level observed in 2007. By contrast, no general decline of the number of nesting eiders was observed from 2007 to 2008 in 75 colonies in the northeastern Baltic Proper and Gulf of Finland. Hence, the spatial distribution of the P. polylepis bloom in 2008 closely matched the observed distribution of extensive non-breeding of female eiders. We suggest that the intensive spring bloom of P. polylepis, either through a toxic or non-toxic pathway, affected the main benthic food of eiders, i.e. blue mussels (Mytilus trossulus x Mytilus edulis), at pre-breeding foraging sites close to the breeding sites, and, subsequently, the body condition of adult female eiders and their breeding propensity.

  • 274.
    Larsson, Kjell
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Hassellöv, Ida-Maja
    Chalmers tekniska högskola.
    Även lite olja kan göra stor skada i havsmiljön2014In: Sjöfarten kring Sverige och dess påverkan på havsmiljön, Göteborg: Havsmiljöinstitutet , 2014, , p. 2p. 8-9Chapter in book (Other academic)
    Abstract [sv]

    Även små oljeutsläpp från fartyg kan få stora negativa effekter på havsmiljön. Hur stora effekterna blir beror på var och när utsläppen sker. Bättre rutiner och skärpt lagstiftning har lett till att mängden utsläppt olja har minskat under de senaste decennierna. Men antalet utsläpp är fortfarande högt och illegala oljeutsläpp sker i stort sett dagligen runt Sveriges kuster.

  • 275.
    Larsson, Kjell
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Karlsson, Pär
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Fartygstrafik i och nära skyddade och känsliga havsområden runt Gotland och Öland2018Report (Other academic)
    Abstract [sv]

    Den internationella fartygstrafiken i Östersjön och inte minst i havsområdet runt Gotland och Öland är mycket intensiv och förväntas öka i omfattning under kommande år. Sjöfarten behöver tillgång till utrymme på havet i form av ändamålsenliga och säkra fartygsrutter. Intensiv fartygstrafik medför dock påverkan på havsmiljön på grund av driftsrelaterade utsläpp till luft och vatten. Intensiv trafik medför även risker för kollisioner, grundstötningar och andra fartygsolyckor som kan ge upphov till mycket stor miljöpåverkan.

     

    Sverige har liksom de flesta av världens länder i enlighet med internationella konventioner ett uppdrag att skydda minst 10 % av havet. Införandet av marina reservat och nationalparker innanför svensk territorialgräns, och av marina Natura 2000-områden innanför territorialgräns och i svensk ekonomisk zon enligt nationell lagstiftning och EU-direktiv, är ett led i uppdraget. Andra internationella konventioner reglerar vilka åtgärder som kan vidtas för att styra fartygstrafik eller för att rekommendera sjöfarten att undvika vissa havsområden.

     

    Havsplanering är ett verktyg för att styra det rumsliga nyttjandet av havet och för att reducera konflikter mellan olika samhällsintressen, t.ex. mellan behovet av sjöfart och behovet av att skydda havsmiljön och marin biologisk mångfald. För att på ett effektivt sätt kunna havsplanera och förbättra och utöka skyddet av värdefulla marina områden krävs kunskap om den påverkan som mänskliga aktiviteter, bland annat sjöfart, har på områdena. Ett första steg är att identifiera de havsområden där fartygstrafiken är mycket intensiv, där fartyg passerar genom eller nära särskilt känsliga områden, där fartyg med särskilt farlig last passerar eller där många fartyg ankrar under längre perioder.

     

    Syftet med rapporten är att sammanställa information om fartygstrafik i och nära skyddade och känsliga havsområden runt Gotland och Öland. I rapporten beskrivs först hur analyser av fartygstrafik kan genomföras med hjälp av lagrade AIS-data. Därefter beskrivs fartygstrafiken i centrala Östersjön och i särskilda fokusområden runt Gotland och Öland. Avslutningsvis diskuteras risker med fartygstrafik i känsliga havsområden och hur konflikter mellan sjöfartens behov och marint områdesskydd kan reduceras. Rapporten har producerats inom projektet ”Marina skyddsvärden runt Gotland och Öland ” som letts av Länsstyrelsen i Gotlands län.

  • 276.
    Larsson, Kjell
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Karlsson, Pär
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Population trends and threats from ship traffic to long-tailed ducks in the Baltic Sea2016In: Progress in Marine Conservation in Europe 2015 / [ed] von Nordheim, H. and Wollny-Goerke, K, Bundesamt für Naturschutz (BfN) , 2016, p. 205-210Conference paper (Refereed)
    Abstract [en]

    The long-tailed duck Clangula hyemalis is a small sea duck that breeds in Arctic tundra regions and winter in marine and brackish waters. Surveys indicate substantial declines in numbers in recent decades and the species is now classified by IUCN as globally threatened in the category “vulnerable”. The largest of the four recognized long-tailed duck populations is the West Siberian / North European population. Birds belonging to the WS/NE population breed in northern Russia and northern Scandinavia and overwinter mainly in the Baltic Sea. An International Single Species Action Plan for the long-tailed duck has also recently been developed by specialists under the auspices of AEWA (Agreement on the Conservation of African-Eurasian Migratory Waterbirds) (HEARN et al. 2015)

    Two Baltic wide surveys have shown that the WS/NE population has decreased very rapidly from approx. 4.3 million birds in 1992-93 to approx. 1.5 million birds in 2007-2009 (DURINCK et al. 1994; SKOV et al. 2011). Although there is some uncertainty regarding the overall level of the population size estimates it is believed that the difference between the estimates accurately reflects the trend between the mid 1990s and late 2000s. A further decline also after 2009 can be assumed as the mean proportion of juveniles in the wintering population has been low since 2009. The recent decline of the WS/NE population can most likely be explained by a combination of factors affecting both the productivity at the Arctic breeding grounds and the adult mortality in the wintering areas in the Baltic Sea.

    Four important anthropogenic threats affecting the wintering birds have been recognised, namely,

    1. operational oil spills from ships at core wintering sites,

    2. by-catches in fishery,

    3. hunting and

    4. disturbance at and exploitation of offshore mussel banks.

    Mortality due to by-catches has decreased but is still high (BELLEBAUM et al. 2013). Hunting mortality is fairly well known and can be regulated if agreements are reached. Displacement of wintering long-tailed ducks from good feeding areas might be more important in future if planned large scale wind farms will be established at core wintering sites, i.e. at offshore banks.

    In this note one of the four recognised anthropogenic threats, i.e. the threat from intensive shipping activities is elucidated. More specifically, an analysis of ship traffic within and close to two marine Natura 2000 sites is presented. The analysed sites, the Hoburgs bank and the Northern Midsjö bank, are two of the most important wintering sites for long-tailed ducks in the Baltic Sea. Several hundred thousand long-tailed ducks, which is a significant part of the global population, have been observed wintering within these areas in recent years (SKOV et al. 2011, NILSSON 2012). Possible methods to reduce the threat from ship traffic are also discussed.

  • 277.
    Larsson, Kjell
    et al.
    Uppsala University, Sweden.
    Tegelström, Håkan
    Uppsala University, Sweden.
    Forslund, Pär
    Uppsala University, Sweden.
    Intraspecific nest parasitism and adoption of young in the barnacle goose: effects on survival and reproductive performance1995In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 50, no 5, p. 1349-1360Article in journal (Refereed)
    Abstract [en]

    DNA fingerprinting was used to determine the proportion of extra-pair young in a population of barnacle geese, Branta leticopsis, breeding in the Baltic area, Sweden. Of 137 analysed fledged young 17% were found to be extra-pair young. One or more extra-pair young were found in 27% of the 63 analysed families. The proportion of extra-pair young differed between years. No case of extra-pair fertilization was detected. All extra-pair young at fledgling originated either from intraspecific nest parasitism or from adoptions of foreign hatched young. Broods with extra-pair young at fledgling were significantly larger than broods without extra-pair young. However, the number of within-pair young did not differ significantly in broods with and without extra-pair young. Body mass, survival or subsequent reproductive performance did not differ between parents with and without extra-pair fledged young. Post-fledgling survival and age at first breeding were not significantly different between the three analysed classes of fledged young, i.e., within-pair young in families without extra-pair young, within-pair young in families with at least one extra-pair young, and extra-pair young. It is concluded that possible costs or benefits associated with caring for extra-pair fledged young are small or absent in this population.

  • 278.
    Larsson, Kjell
    et al.
    Uppsala University, Sweden.
    Tydén, Lars
    Uppsala University, Sweden.
    Effekter av oljeutsläpp på övervintrande alfågel Clangula hyemalis vid Hoburgs bank i centrala Östersjön mellan 1996/97 och 2003/04: Effects of oil spills on wintering Long-tailed Ducks Clangula hyemalis at Hoburgs bank in central Baltic Sea between 1996/97 and 2003/042005In: Ornis Svecica, ISSN 1102-6812, Vol. 15, p. 161-171Article in journal (Refereed)
    Abstract [en]

    The Baltic Sea is an important marine area for wintering birds. Surveys in the 1990s showed that more than 25 % of the European Long-tailed Duck Clangula hyemalis population wintered at Hoburgs bank and east of Gotland. A shipping route with very frequent traffic goes from southwest Baltic Sea via Öland, Hoburgs bank and east of Gotland to the Gulf of Finland. In year 2000 about 58 500 ships passed east of Öland along this route. Hundreds of oils spills are registered along the route each year. Weekly surveys of oiled birds at southern Gotland and analyses of birds that had drown in fish nets showed that tens of thousands of ong-tailed Ducks were injured by oil each year in central Baltic Sea. Of 998 birds that drowned in fish nets at Hoburgs bank 11.8 % were found to have oil in the plumage. There was no clear relationship between the number of oiled birds observed and the number of registered oil spills in different years. Many sea duck have a life history in which variable or low productivity is compensated for by relatively high adult survival. This makes sea duck populations very susceptible to extra adult mortality caused by oil spills.

  • 279.
    Larsson, Kjell
    et al.
    Uppsala University, Sweden.
    Van der Jeugd, Henk P.
    Uppsala University, Sweden.
    Continuing growth of the Baltic barnacle goose population: Number of individuals and reproductive success in different colonies1997In: Research on arctic geese: proceedings of the Svalbard Goose Symposium, Oslo, Norway, 23-26 September 1997 / [ed] Fridtjof Mehlum, Jeff Black, Jesper Madsen, Norsk Polarinstitutt , 1997, Vol. 200, p. 213-219Conference paper (Refereed)
    Abstract [en]

    The Baltic barnacle goose population increased rapidly after 1971, when the first breeding attempt was observed off the eastern coast of Gotland, Sweden. In 1997, about 3,990 pairs bred along the Baltic coast in Sweden, western Estonia and southern Finland. The majority of these pairs, about 3,490 pairs, were found breeding in colonies along the eastern coasts of Gotland and Oland, Sweden. The total population size at the end of July in 1997 was estimated to be approximately 17,000 individuals. The production of fledged young per breeding pair was negatively related to the size of colonies, although the production varied greatly among different colonies. In 1997, the largest Baltic colony hosted more than 50% of the total number of breeding pairs but produced less than 15% of the total number of fledged young. This finding points out the need to consider different colonies as separate demographic units when studying regulation processes in populations of colonially breeding geese. In the future, we find it most probable that the Baltic population will continue to increase and that new colonies will be established. We also expect that the number of Baltic barnacle geese eventually will be limited by the availability of predator-safe grazing grounds with short, protein rich grass which families with newly hatched goslings are dependent on.

  • 280.
    Larsson, Per
    Limnology, Department of Ecology, University of Lund .
    Atmospheric deposition of persistent pollutants governs uptake in freshwater zooplankton1989In: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 23, no 10, p. 2151-2158Article in journal (Refereed)
    Abstract [en]

    The atmospheric fallout of PCBs, ∑DDT and γ-HCH (lindane) to a pond in southern Sweden was studied in relation to uptake by freshwater Zooplankton. The extent of the atmospheric deposition of PCBs and lindane was reflected in the uptake by the Zooplankton; high deposition in the spring and autumn resulted in high uptake by the organisms while a lower uptake during summer was a result of lower deposition. The atmospheric deposition of ∑DDT was dominated by p,p-DDT, p,p-DDE and o,p-DDT, while p,p-DDE and p,p-DDD were dominant in Zooplankton. These differences in ∑DDT composition are probably attributed to microbial conversion; as a result, levels in the Zooplankton appeared not to be governed by atmospheric deposition. The availability of the previously airborne, persistent pollutants to Zooplankton was a function of the compounds chemical properties, e.g. water solubility, and the form of deposition. The results show that atmospheric deposition is an important route by which persistent pollutants are transported to Holarctic, aquatic ecosystems. 

  • 281.
    Larsson, Per
    Institute of Limnology, University of Lund, Box 65, S-221 00 Lund, Sweden.
    Contaminated sediments of lakes and oceans act as sources of chlorinated hydrocarbons for release to water and atmosphere1985In: Nature, Vol. 317, p. 347-349Article in journal (Refereed)
    Abstract [en]

    Atmospheric transport is a major route for entry of chlorinated, aromatic hydrocarbons into aquatic ecosystems. Once in the water, the compounds are readily taken up by the biota and distributed in the food webs. Major fractions of the compounds are deposited in the sediment1, and it had been thought that most persistent contaminants are inactivated in this way as a consequence of their lipophilic properties. However, results from recent laboratory studies2,3 raise the possibility that aquatic sediments may not be the final sink for the substances but may rather act as a source through redistribution of the compounds to water and the atmosphere. Polychlorinated biphenyls (PCBs) may be regarded as 'tracers' for these contaminants in the ecosystem, and I studied the transport of PCBs from sediment to water and air in two artificial ponds in the field. The transport from the sediment followed a seasonal cycle; higher concentrations of PCBs in water and air were recorded in the summer and lower in the winter. PCB concentrations in the air over the ponds were positively correlated with PCB levels in the water. My results show that contaminated sediments may act as a source of chlorinated hydrocarbons released into the environment. 

  • 282.
    Larsson, Per
    Lund university.
    Havs- och sjöbottnar förgiftar luften1986In: Forskning och Framsteg, Vol. 8, p. 4-8Article in journal (Other (popular science, discussion, etc.))
  • 283.
    Larsson, Per
    Lund university.
    Malen - Smålands storsjöodjur1982In: Jakt och fångst i Småland / [ed] Fritz Hovne, Växjö: Kronobergs läns hembygdsförb. i samarbete med Smålands mus. , 1982, , p. 149-154p. 149-154Chapter in book (Other academic)
  • 284.
    Larsson, Per
    Institute of Limnology, University of Lund, Box 3060, S-220 03, Lund, Sweden.
    PCBs (Clophen A 50) change composition when transported from sediment to air in aquatic model systems1985In: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 9, no 2, p. 81-94Article in journal (Refereed)
    Abstract [en]

    PCBs (Clophen A 50) were added to the sediment of laboratory model systems composed of sediment, water, benthic macroinvertebrates and fish. Part of the PCBs left the sediment and a concentration of 0·2–0·7 μg litre−1 was obtained in the water.The transport of PCBs from water to air includes at least two processes: volatilization and jet drop transport. Volatilization (as indicated by PCBs trapped on polyurethane foam filters) resulted in a transport of 0·2–1·0 μg PCBs a week to air. Less chlorinated PCBs, i.e. tetrachlorobiphenyls, were transported to the air to a greater extent than more chlorine-substituted PCBs.Transport of PCBs by jet drops from bursting bubbles as indicated by the amount of PCBs found on jet drop impactors) was of the same magnitude as volatilization, but the proportion of PCB compounds trapped by the impactor plates was identical with that of sediment and water. The process seems mainly to transfer PCBs containing bulk water and particles to the air.The results suggest that the contaminated sediment of lakes and watercourses may act as a source of PCBs to the atmosphere. 

  • 285.
    Larsson, Per
    Lund university.
    Sedimentation of polychlorinated biphenyls (PCBs) in limnic and marine environments1984In: Water research, Vol. 18, no 11, p. 1389-1394Article in journal (Refereed)
    Abstract [en]

    The sedimentation rates of PCBs in two southern Swedish lakes and a coastal bay in the southern Baltic were determined using sediment traps. The rates were similar at the three locations and ranged from 1.2 to 10.9 μg PCBs m−2 month−1 during summer. The source for PCBs in sedimenting material is probably the atmosphere. PCB concentrations in sedimenting material were higher than those in surface sediment. This may be due to recirculation of sediment-bound PCBs.

    The reproducibility of collecting by sediment traps was examined by deploying duplicate traps simultaneously. There were no significant differences in PCB concentration of sedimenting material between traps placed in duplicate. Concentrations of PCBs in the different collecting vessel was similar within one trap. 

  • 286.
    Larsson, Per
    Lunds Universitet.
    Transport of 14C-labelled PCB compounds from sediment to water and air in laboratory model systems1983In: Water research, Vol. 17, no 10, p. 1317-1326Article in journal (Refereed)
    Abstract [en]

    Tetra-, hexa- and octachlorobiphenyls were added to aquatic model systems composed of undisturbed sediment cores with an overlying water phase. Using impactor plates transport of the compounds from sediment to air was observed. About one per cent of the sediment-bound PCBs recovered in the systems left the water by jet drops from bursting bubbles. The transport of PCBs from the sediment to the air was nearly constant over time, with a transport rate of 0.62 μg · dm−2 week−1 for tetrachlorobiphenyl. Tetrachlorobiphenyl was mobile in systems with and without macroinvertebrates and in those fixed with HgCl2. Hexa- and octachlorobiphenyls were transported from sediment to water mainly by bioturbation processes. The two latter substances had a higher adsorption to particles than tetrachlorobiphenyl. Compared to tetrachlorobiphenyl, more hexa- and octachlorobiphenyls accumulated in chironomids and tubificids. 

  • 287.
    Larsson, Per
    Lund university.
    Transport of PCBs from aquatic to terrestrial environments by emerging chironomids1984In: Environmental pollution, Vol. 34, no 3, p. 283-289Article in journal (Refereed)
    Abstract [en]

    The transport of PCBs from sediment to air by emerging chironomids (Chironomus plumosus-type) was studied in aquatic laboratory model systems. Uptake of PCBs from the sediment by chironomid larvae was directly related to the concentration of PCBs in the sediment. When the larvae metamorphosed to adults the PCB compounds were concentrated and transferred from the aquatic to the terrestrial environment. A minor part of the compounds was retained in the exuviae. In a field study, transport of PCBs by chironomids from the aquatic to the terrestrial environment was estimated at 20 μg PCBs m−2 year−1. The results suggest an additional way in which terrestrial predators that feed on emerging aquatic insects, whose larval stage is in contaminated sediment, are exposed to organochlorine residues. 

  • 288.
    Larsson, Per
    Department of Ecology, Limnology Section, University of Lund.
    Uptake of polychlorinated biphenyls by the macroalga Cladophora glomerata1987In: Bulletin of Environmental Contamination and Toxicology, ISSN 0007-4861, E-ISSN 1432-0800, Vol. 38, no 1, p. 58-62Article in journal (Refereed)
  • 289.
    Larsson, Per
    Dept of Limnology, Univ. of Lund.
    Uptake of sediment released PCBs by the eel, Anguilla anguilla, in static model systems1984In: Ecological bulletins, ISSN 0346-6868, Vol. 36, p. 62-67Article in journal (Refereed)
    Abstract [en]

    PCBs (Clophen A 50) were added to sediment (1 ^tg g-1 fw) of 60-1 aquaria thatcontained sediment, water, benthic macroinvertebrates and eels. To compare uptakeof PCBs in eels that fed on macroinvertebrates in the sediment to eels that wereseparated from the sediment, the bottom of some systems were screened off with anet.In all systems, except the control, PCBs were transported from the sediment to thewater so that a concentration of 0.1-0.7 n-gl-1 was obtained. The transport wasdependent on benthic macroinvertebrates and was related to the transfer of particlesacross the sediment/water interface.PCBs in eels that were separated from the sediment ranged from 2.5 to 8.9 ug g"1 fwafter 77 d. In eels that were allowed to feed in the sediment the concentration was7.2-14.1 M-gg-1The results show that PCBs were released from sediment to the water, and weretaken up by the eels directly from the water presumably as a result of water/fatpartitioning processes in the fishes. 

  • 290.
    Larsson, Per
    UNIV LUND, INST LIMNOL.
    Zooplankton and fish accumulate chlorinated hydrocarbons from contaminated sediments1986In: Canadian Journal of Fisheries and Aquatic Sciences, ISSN 0706-652X, E-ISSN 1205-7533, Vol. 43, no 7, p. 1463-1466Article in journal (Refereed)
    Abstract [en]

    Polychlorinated biphenyls (PCBs) originating from the sediment were taken up by zooplankton and fish in artificial ponds in the field. PCB uptake in zooplankton was concentration dependent, as levels of the residues in water varied seasonally. Planktivorous fish accumulated the compounds to high levels at high summer concentrations of PCBs in the water, after which elimination was slow. Levels of PCBs in benthic fishes continuously increased during the 1.5-yr study. The results show that chlorinated hydrocarbons deposited in sediments are available to aquatic organisms. Decreasing levels of PCBs in daphnids in the autumn-winter of 1983 and in the summer of 1984 may be due to different generations of daphnids being exposed to different concentrations of PCBs in the water, thus establishing new partitionings. 

  • 291.
    Larsson, Per
    et al.
    Limnology, Department of Ecology, University of Lund .
    Hamrin, S
    Okla, L
    Factors determining the uptake of persistent pollutants in an eel population (Anguilla anguilla L.) of a eutrophic lake1991In: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 69, no 1, p. 39-50Article in journal (Refereed)
    Abstract [en]

    The distribution of persistent pollutants in an eel population from a eutrophic lake of southern Scandinavia was examined. The origin of PCBs, DDT, DDE and lindane found in the fish was most likely the atmosphere. The most important factors for uptake of the chlorinated hydrocarbons was age (exposure time), growth rate and fat content. The life cycle of the eel is unique with a stage in freshwater when energy reserves (fat stored in muscular tissue) and lipophilic pollutants are accumulated. This stage is followed by a long migration to the spawning areas in the Sargasso Sea when pollutants are released from the fat deposits. These two stages followed by a once-in-a-lifetime spawning behaviour, makes the eel especially vulnerable to persistent pollutants. The effects of persistent pollutants combined with the eel's unusual life cycle may explain the decline in the eel population in northern Europe in recent decades. 

  • 292.
    Larsson, Per
    et al.
    Limnology, Department of Ecology, University of Lund .
    Hamrin, S
    Okla, L
    Fat content as a factor inducing migratory behaviour in the eel (Anguilla anguilla L.) to the Sargasso Sea1990In: Die Naturwissenschaften, ISSN 0028-1042, E-ISSN 1432-1904, Vol. 77, no 10, p. 488-490Article in journal (Refereed)
  • 293.
    Larsson, Per
    et al.
    Limnology, Department of Ecology, University of Lund .
    Järnmark, C
    Broman, D
    Lexén, K
    Critical processes for transport of PCB, lindane and PAH to and in the Baltic Sea1990In: Large-scale environmental effects and ecological processes in the Baltic Sea: research programme for the period 1990-1995 and background documents / [ed] Fredrik Wulff, Solna: Statens naturvårdsverk , 1990, , p. 95-123p. 95-123Chapter in book (Other academic)
  • 294.
    Larsson, Per
    et al.
    Limnology, Department of Ecology, University of Lund .
    Lemkemeier, K
    Microbial mineralization of chlorinated phenols and biphenyls in sediment/water systems humic and clear-water lakes1989In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 23, no 9, p. 1081-1085Article in journal (Refereed)
    Abstract [en]

    The microbial mineralization of three chlorophenols and a PCB mixture was studied using natural bacterial assemblages in laboratory model systems. The systems consisted of water and surface sediment from two lake types: one with a high content of humic substances and the other with a low content. Aerobic mineralization of the 14C-ring-labelled compounds was determined as production of 14CO2 in the systems. The mineralization rates of 3,4-dichlorophenol and 2,4,5-trichlorophenol were higher in humic cultures whereas pentachlorophenol showed higher rates in clear-water cultures. Mineralization of PCBs in the systems was low. Compared with microbial mineralization rates in cultures containing only lake water, the addition of sediment resulted in a decrease in DCP and TCP mineralization. Pentachlorophenol was mineralized at considerably higher rates in the presence of sediment. 

  • 295.
    Larsson, Per
    et al.
    Institute of Limnology, University of Lund.
    Lindegren, A
    Animals need not to be killed to reveal their body-burdens of chlorinated hydrocarbons1987In: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 45, no 1, p. 73-78Article in journal (Refereed)
    Abstract [en]

    The levels of persistent, lipophilic pollutants in different organs and body-fluids of birds are governed by partitioning, i.e. the levels are correlated. This implies that it may be possible to estimate the total body-burden of chlorinated hydrocarbons, without sacrificing the animals, by examining the levels in secretory fluid. This hypothesis was tested on the goosander, a fish-eating waterfowl. We found that levels of PCB and DDE in secretions from the uropyginal gland were linearly related to levels in the breast muscle. Thus, by estimating the amounts of persistent pollutants in water-repellent secretions, the total body-burden could be calculated. 

  • 296.
    Larsson, Per
    et al.
    Institute of Limnology, University of Lund.
    Okla, L
    An attempt to measure the flow of chlorinated hydrocarbons, such as PCBs, from water to air in the field1987In: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 44, no 3, p. 219-225Article in journal (Refereed)
    Abstract [en]

    A field sampling device to study the transport of aromatic, persistent chlorinated hydrocarbons from water to air was constructed. It was tested in large, outdoor artificial ponds contaminated with polychlorinated biphenyls (PCBs). The PCB compounds volatilised to air at a rate of 0·9 to 9·6 ng m−2 h−1 depending on levels of PCBs in the water and water temperature. 

  • 297.
    Larsson, Per
    et al.
    Limnology, Department of Ecology, University of Lund.
    Okla, L
    Atmospheric transport of chlorinated hydrocarbons to Sweden 1985 compared to 19731989In: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 23, no 8, p. 1699-1711Article in journal (Refereed)
    Abstract [en]

    The atmospheric fallout of DDT and DDE (ΣDDT) over Sweden has decreased during the last decade. Today long-range transport from southern sources outside the country dominates the inflow. This was reflected in a decreasing south-to-north gradient of the compounds in atmospheric deposition and in the lower atomosphere. The fallout of PCBs was similar in 1984–1985 and 1972–1973, and today local contamination by combustion is more prominent than it was 10 years ago, even though PCB restrictions have been in force during the interim. Since PCB deposition is higher in the coastal areas than in the inland regions, other sources, such as volatilization from the seas and long-range transport also contribute to PCBs in fallout.

    The levels of PCB and ΣDDT in the lower atmosphere were positively correlated with temperature. Consequently, the compounds tended to be in the gas phase during the warmer summer period whereas during winter they were more liable to be adsorbed to particles, partition to airborne water and contribute in fallout.

    From each sampling station a chromatographic 'fingerprint' of pollutants in airborne fallout and in the lower atmosphere was obtained. The fingerprint was the combined result of the station's location and climate.

    The results show that considerable amounts of chlorinated pollutants are being transported to and within Sweden via the atmosphere. 

  • 298.
    Larsson, Per
    et al.
    Limnology, Department of Ecology, University of Lund.
    Okla, L
    Ryding, S-O
    Westöö, B
    Contaminated sediment as a source of PCBs in a river system1990In: Canadian Journal of Fisheries and Aquatic Sciences, ISSN 0706-652X, E-ISSN 1205-7533, Vol. 47, no 4, p. 746-754Article in journal (Refereed)
    Abstract [en]

    The transport of PCBs (Aroclor 1242) in a river system in southern Sweden was governed by outflow from sediment in a 26-ha contaminated lake. Experiments in the lake revealed that 14 g PCBs/d escaped from the sediment, while sedimentation was 3 g PCB/d. Volatilization of PCBs from the lake surface was 0.02 g/d, which was considerably higher than the atmospheric fallout . The majority of the sediment-desorbed compounds (80%) remained at the river mouth, 60 km downstream, and entered the Baltic Sea. Desorption increased the ratio of tetrachlorobiphenyls to pentachlorobiphenyls in the water. Transport across the water/air interface was higher for trichlorobiphenyls, while atmospheric deposition was dominated by penta- and hexachlorobiphenyls. Therefore, the sediment of the lake acted as a source of PCBs entering the river system as well as the atmosphere. 

  • 299.
    Larsson, Per
    et al.
    Department of Ecology, University of Lund.
    Okla, L
    Tranvik, Lars
    Microbial degradation of xenobiotic, aromatic pollutants in humic water1988In: Applied and Environmental Microbiology, ISSN 0099-2240, E-ISSN 1098-5336, Vol. 54, no 7, p. 1864-1867Article in journal (Refereed)
    Abstract [en]

    The microbial degradation of a number of 14C-labeled, recalcitrant,aromatic pollutants, including trichloroguaiacol and di-, tri-,and pentachlorophenol, was investigated in aquatic model systemsin the laboratory. Natural, mixed cultures of microorganismsin the water from a brown-water lake with a high content ofhumic compounds mineralized all of the tested substances toa higher degree than did microorganisms in the water from aclear-water lake. Dichlorophenol was the most rapidly degradedpollutant. 

  • 300.
    Larsson, Per
    et al.
    Limnology, Department of Ecology, University of Lund .
    Okla, L
    Woin, P
    Atmospheric transport of persistent pollutants governs uptake by Holarctic biota1990In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 24, no 10, p. 1599-1601Article in journal (Refereed)
    Abstract [en]

    The atmospheric deposition of PCBs, DDT, and lindane,governed uptake in terrestrial biota in the Scandinavianpenninsula. Mammalian herbivores and predators as wellas predatory insects contained higher levels of pollutantsat locations where the fallout load was high than at stationswhere atmospheric deposition was lower, and the twovariables were significantly correlated. 

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