SwePub
Sök i SwePub databas

  Extended search

Träfflista för sökning "WFRF:(Litzén Anders) "

Search: WFRF:(Litzén Anders)

  • Result 1-5 of 5
Sort/group result
   
EnumerationReferenceCoverFind
1.
  • Helander, Björn, 1946-, et al. (author)
  • The Role of DDE, PCB, Coplanar PCB and Eggshell Parameters for Reproduction in the White-tailed Sea Eagle (Haliaeetus albicilla) in Sweden.
  • 2002
  • In: Ambio. - 0044-7447 .- 1654-7209. ; 31:5, s. 386-403
  • Journal article (peer-reviewed)abstract
    • The reproduction of white-tailed sea eagles was monitoredin1964–1999 in 3 differently contaminated sub-populations: BalticSea coast (Bp), inland central Sweden (Ip) and Lapland (Lp). 249dead eggs from 205 clutches were obtained for analyses of DDEand PCBs and for eggshell measurements. A desiccation index(Di) value was calculated for each egg as a measure of waterloss through the shell. In the highly contaminated Bp, p,p´-DDEconcentrations in the eggs decreased continuously and 5-foldduring the study period and PCB concentrations decreased 3-fold from the mid 1980s. The PCB pattern changed slightly overtime towards more high-chlorinated congeners but the relativetoxicity of the PCB mixture, expressed as 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQ), remained constant and TEQcan be assumed to have decreased in a similar way as PCB overtime. Productivity (P), shell thickness (St), shell index (Si) and Diincreased over time in the Bp but no change in Di or productivityoccurred in the Lp, where residue concentrations were 5–8 timeslower. P of the Bp was not correlated to St or Si but was negatively correlated to Di, DDE and PCB. An S-shaped doseresponse relationship was indicated between P and DDE. After1988, when the PCB/DDE ratio was considerably higher thanpreviously, PCB but not DDE concentrations were significantlyhigher in eggs with dead embryos as compared to undevelopedeggs, implying lethal concentrations of PCB, and a LOEL of 320pg g–1 TEQ is suggested for embryo mortality. In a subset of 21eggs, representing productive and unproductive females, analyzed for a selection of coplanar PCB congeners, tris(4-chlorophenyl) methanol and bis(4-chlorophenyl) sulphone, there wasno evidence for a correlation between P and any of these compounds. A reduction in residue concentrations in old females didnot lead to increased P or improved Di-values, indicating aremaining effect from a previous, higher exposure to contaminants. The inability to reproduce included a high rate ofundeveloped eggs, indicating effects at a prezygotic stage. Pshowed the strongest correlation with Di, and Di was moststrongly correlated to DDE. Thus, the remaining effect of previousexposure resulted in a stronger correlation to the symptom (Di)rather than to the suggested causative agent (DDE). LOEL valuesfor depressed P were estimated at 120 µg g–1 DDE and 500 µgg–1 PCB (lipid basis). It is concluded that the major reason fordepressed P during the study period was DDE, but that effectsalso from PCB were largely concealed by the effects from DDE.
  •  
2.
  • Ytreberg, Agnes, et al. (author)
  • God havsmiljö 2020 : Marin strategi för Nordsjön och Östersjön Del 3: Övervakningsprogram
  • 2014
  • Reports (other academic/artistic)abstract
    • Havsmiljöförordningens övergripande mål är att upprätthålla eller uppnå en god miljöstatus i de svenska förvaltningsområdena Nordsjön och Östersjön till år 2020. En av uppgifterna i den första förvaltningsperioden är att fastställa övervakningsprogram.God miljöstatus baseras på ett ramverk av så kallade deskriptorer som anges i havsmiljödirektivet, det vill säga det EU-direktiv som i Sverige genomförs genom havsmiljöförordningen. Deskriptorerna beskriver god miljöstatus på en övergripande nivå för elva temaområden. Till varje deskriptor hör en rad kriterier som anger vad som ska ingå i en bedömning av miljöstatus. Utifrån de elva deskriptorerna har Sverige fastställt 13 övervakningsprogram. Sex program utgår ifrån olika biodiversitetsteman som berörs av en upp till tre deskriptorer, medan de övriga sju programmen utgår ifrån de deskriptorer som är mer inriktade mot belastning och miljöförändring.För varje program har ett antal underprogram föreslagits baserat på den nuvarande övervakningen och/eller planerad övervakning. Övervakning som ingår i programmen ska vara pågående och data ska vara tillgängliga. I programmen ingår nationell och regional miljöövervakning inklusive verksamhetsutövares recipientkontroll. Dessutom ingår annan typ av datainsamling som till exempel inventeringar av tumlare och uppgifter om omfattningen av mänskliga aktiviteter som orsakar belastning och miljöförändringar. Enligt havsmiljödirektivet ska övervakningen fånga upp tillstånd och miljöförändringar, belastning och omfattning av aktiviteterna som orsakar belastningen samt effekter av åtgärder. Eftersom nästa steg i havsförvaltningscykeln är att fastställa åtgärdsprogram kommer övervakning för att följa upp åtgärder att läggas till övervakningsprogrammen först under nästa förvaltningscykel.I beskrivningarna av programmen framgår hur den nuvarande övervakningen motsvarar de krav som ställs på dataunderlag genom havsmiljödirektivets bilaga III samt genom deskriptorer, kriterier, indikatorer och beslutade miljökvalitetsnormer. I dagens övervakning saknas bland annat tillräcklig övervakning för uppföljning av livsmiljöers tillstånd och utbredning. För marint avfall, buller och främmande arter saknas nationellt samordnad övervakning, men det görs regionala insatser och ett antal projekt har genomförts eller påbörjats för att öka kunskapen om hur övervakning bäst ska utformas. För de program som har pågående övervakning beskrivs utvecklingsbehoven för att förbättra underlaget för de återkommande tillståndsbedömningarna.Övervakningsprogrammet som fastställs under 2014 utgör således inte ett fast program för kunskapsinhämtning. Bristerna kommer att beaktas i det fortsatta genomförandet av havsmiljöförordningen där utveckling av indikatorer och övervakning kommer att ske kontinuerligt.
  •  
3.
  • Bignert, Anders, et al. (author)
  • Temporal trends of organochlorines in Northern Europe, 1967–1995. Relation to global fractionation, leakage from sediments and international measures
  • 1998
  • In: Environmental Pollution. - 0269-7491 .- 1873-6424. ; 99:2, s. 177-198
  • Journal article (peer-reviewed)abstract
    • The time trend monitoring of organochlorine pollution was carried out in Sweden since the late 1960s. This report presents data on concentrations of DDT, PCB, HCHs and HCB in biota samples collected and analysed annually. All the matrices and compounds studied show a significant decrease over time. The data cover severely polluted Swedish marine and fresh water in southern Sweden as well as locally unpolluted waters in remote northern Arctic regions of Sweden. A total of 13 time series representing different locations and species are presented for the different pollutants. The period studied covers the time when pollution was serious as well as the time of recovery. All monitoring activities were carried out at the same laboratories over the entire study period, which means that comparability over time is good in the sets of data presented. The various time trends show a convincing agreement with trends and annual change over time, although the concentrations differ between the species and locations investigated, the highest concentrations being in the south. Since the annual changes are normally similar regardless of locations and species, spatial variations in concentrations remain over time, although concentrations are lower today. The onset of changes in concentrations over time can be related to international measures or other circumstances that lowered releases into the environment. Similarities in the annual changes, as well as the time when changes began, are discussed with respect to suggested hypotheses on the fate of the investigated organochlorines. It was not possible to verify that the oxygenation of anoxic sediments mobilised old pollution in Baltic sediments. Neither was it possible to conclude that eutrophication has caused a measurable effect on the rate and timing of the decreases. Finally, long-range transport to Arctic regions seems to be due more to a one step transport than to the ‘Grass-hopper’ effect. The comprehensive database used, clearly shows how important it is to have datasets big enough to describe between-year variation before attempting to evaluate the time trend. In addition, if between-year variation is not known, it is then also difficult to evaluate spatial variation on the basis of single year observations.
  •  
4.
  • Johansson, S. G, et al. (author)
  • Comparison of New Experimental and Astrophysical F-values For Some Ru-ii Lines, Observed In Hst Spectra of Chi-lupi
  • 1994
  • In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 421:2, s. 809-815
  • Journal article (peer-reviewed)abstract
    • We report on experimental absolute oscillator strengths for 18 UV lines of Ru II, obtained by combining laser-induced fluorescence measurements of radiative lifetimes and branching fractions from line intensities in a calibrated Fourier-transform spectrum. HST/GHRS observations of the spectrum of the sharp-lined B star chi Lupi contain six of these lines, for which ''astrophysical'' relative f-values have been determined. The agreement is within 0.10 dex for a Ru abundance of log N(Ru)/N(H) = -7.90, which is 2.3 dex above the solar abundance.
  •  
5.
  • Sikström, Carl Martin, et al. (author)
  • Uncertainty of oscillator strengths derived from lifetimes and branching fractions
  • 2002
  • In: Journal of Quantitative Spectroscopy and Radiative Transfer. - 0022-4073. ; 74:3, s. 355-368
  • Journal article (peer-reviewed)abstract
    • A widely used method for determination of transition probabilities and oscillator strengths is based on measurements of branching fractions and radiative lifetimes. In the present work the different sources of uncertainty in branching fraction measurements using Fourier transform spectroscopy and lifetime measurements using laser induced fluorescence are discussed. A detailed description is presented of how the uncertainties should be combined to provide a well-defined uncertainty of the derived quantity. Finally, an example shows how the individual uncertainties can be presented in an "uncertainty budget".
  •  
Skapa referenser, mejla, bekava och länka
  • Result 1-5 of 5

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Close

Copy and save the link in order to return to this view