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1.
  • Nasr, Patrik, et al. (författare)
  • A rapid, non-invasive, clinical surveillance for CachExia, sarcopenia, portal hypertension, and hepatocellular carcinoma in end-stage liver disease : the ACCESS-ESLD study protocol
  • 2023
  • Ingår i: BMC Gastroenterology. - : BioMed Central (BMC). - 1471-230X. ; 23:1
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Liver cirrhosis, the advanced stage of many chronic liver diseases, is associated with escalated risks of liver-related complications like decompensation and hepatocellular carcinoma (HCC). Morbidity and mortality in cirrhosis patients are linked to portal hypertension, sarcopenia, and hepatocellular carcinoma. Although conventional cirrhosis management centered on treating complications, contemporary approaches prioritize preemptive measures. This study aims to formulate novel blood- and imaging-centric methodologies for monitoring liver cirrhosis patients.METHODS: In this prospective study, 150 liver cirrhosis patients will be enrolled from three Swedish liver clinics. Their conditions will be assessed through extensive blood-based markers and magnetic resonance imaging (MRI). The MRI protocol encompasses body composition profile with Muscle Assement Score, portal flow assessment, magnet resonance elastography, and a abbreviated MRI for HCC screening. Evaluation of lifestyle, muscular strength, physical performance, body composition, and quality of life will be conducted. Additionally, DNA, serum, and plasma biobanking will facilitate future investigations.DISCUSSION: The anticipated outcomes involve the identification and validation of non-invasive blood- and imaging-oriented biomarkers, enhancing the care paradigm for liver cirrhosis patients. Notably, the temporal evolution of these biomarkers will be crucial for understanding dynamic changes.TRIAL REGISTRATION: Clinicaltrials.gov, registration identifier NCT05502198. Registered on 16 August 2022. Link: https://classic. CLINICALTRIALS: gov/ct2/show/NCT05502198 .
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2.
  • Smith, Henrik G., et al. (författare)
  • Slututvärdering av det svenska landsbygdsprogrammet 2007–2013 : Delrapport II: Utvärdering av åtgärder för bättre miljö
  • 2016
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • SammanfattningRapporten är en del av slututvärderingen av Landsbygdsprogram för Sverige 2007-2013 och har tagits fram på uppdrag av Jordbruksverket. Den redovisar resultat och effekter som uppnåddes genom miljö- och klimatåtgärderna inom landsbygdsprogrammet, vilket omfattar samtliga insatser och ersättningar i axel 2, samt miljö- och klimatrelaterade utvärderingsfrågor för en del åtgärder i axel 1 och 3.Med hjälp av vetenskapliga analyser, kunskapsbaserade resonemang och de för varje insats i landsbygdsprogrammet specificerade indikatorerna har bland annat följande EU-gemensamma (QEC) och programspecifika (PSEQ) utvärderingsfrågor besvarats:• QEC 16: I vilken utsträckning har åtgärden bidragit till att förbättra miljösituationen?• CEQ 20: Vilka andra effekter, bl.a. de som rör andra mål/axlar, är kopplade tillgenomförandet av denna åtgärd?• PSEQ 16A: Hur ändamålsenlig och effektiv har den geografiska styrningen avmiljöåtgärden i programmet varit?• PSEQ 20A: I vilken utsträckning har kompetensutvecklingsåtgärderna bidragittill programmets miljömål?• PSEQ 20B: Vad kan man lära sig av hur klimatåtgärderna fungerat när det gällerutformningen och utvärderingen av klimatåtgärder i framtida program?• PSEQ 20C: Vilka sysselsättningseffekter ger miljöåtgärderna?Utredarnas generella slutsats är att landsbygdsprogrammet spelat en stor och i många fall avgörande roll för miljön, t.ex. genom att förhindra nedläggning av jordbruk i områden med svåra förutsättningar för jordbruk, bevara betes- och slåttermarker av värde för biologisk mångfald och skapa och restaurera våtmarker för biologisk mångfald och näringsretention. Detta bidrar till uppfyllelsen av de svenska miljömålen och internationella åtaganden. Även de klimatrelaterade åtgärderna bidrar i viss mån till att uppfylla miljömålen, men en låg anslutning till vissa åtgärder och programmets ensidiga fokus på produktion av förnybar energi (som bortser från ur klimatsynvinkel mycket större biogena utsläppskällor) gör att effekten på miljömålen bedöms som relativt små. Bedömningen av kompetensutvecklingens effekter på miljömålen har försvårats av brist på tillämpningsbart underlag, men utvärderingen av rådgivningsprogrammet Greppa näringen visar att det bidragit till att reducerakvävetillförseln till Östersjön. För en del andra åtgärder är det empiriska underlaget för vilken effekt de har mycket svagt. Detta behöver i sig inte innebära att dessa åtgärder saknar effekt, men gör det svårt att bedöma deras bidrag till uppfyllelsen av miljömålen och begränsar kunskapen om huruvida alternativa utformningar av insatserna skulle ge större effekt.Den explicita geografiska styrningen som förekommer i programmet bedöms generellt som relevant, men dess effekt varierar stort mellan olika åtgärder/insatser och är i vissa fall svårt att utreda. Det finns dock en del åtgärder/insatser som idag saknar explicit geografisk styrning, men där vi bedömer att kostnadseffektiviteten skulle kunna öka markant om man införde en sådan (t.ex. Certifierad ekologisk produktion).Miljöåtgärdernas sysselsättningseffekter har endast kunnat bedömas för ett fåtalåtgärder/insatser (kompensationsbidraget samt ersättningarna för Extensiv vallodling och Skötsel av betesmarker och slåtterängar) och anses generellt vara marginellt positiv. Detta bör dock tolkas med stor försiktighet eftersom bedömningen gjordes enbart via dessa åtgärders effekt på markanvändningen.Miljö- och klimatåtgärders effekterUnder programperioden 2007-2013 innehöll landsbygdsprogrammet en mängd olika åtgärder med syfte att gynna miljö och klimat. Utvärderingen visar att det finns en stor variation i såväl upptaget av de olika åtgärderna som deras effekt. Miljöåtgärdernas syften fokuserar huvudsakligen på att gynna bevarandet av biologisk mångfald, minskat växtnäringsläckage och giftfri miljö. De flesta miljöåtgärder bidrar generellt till att uppnå sitt syfte, men om de gör det på ett kostnadseffektivt sätt har ofta varit svårt och ibland omöjligt att utvärdera. För syftet giftfri miljö har det inte funnits resurser till en djupare utvärdering.Ersättningarna för Skötsel av betesmarker och slåtterängar samt för Certifieradekologisk och kretsloppsinriktad produktion är exempel på insatser med konstaterad positiv effekt på biologisk mångfald. Andra ersättningar, såsom ersättningen för Värdefulla natur- och kulturmiljöer, adresserar visserligen för biologisk mångfald viktiga livsmiljöer, men deras utformning och skötselvillkor har visat sig inte vara anpassade till detta syfte med insatsen. För en del ersättningar saknas tillräckligt kunskap eller dataunderlag för att kunna göra tillfredställande utvärderingar av effekterna på biologisk mångfald. Bland dessa finns exempelvis ersättningarna för Extensiv vallodling och Skötsel av våtmarker.Minskat näringsämnesläckage och miljömålet Ingen övergödning fanns som syfte för flera insatser inom åtgärden Miljövänligt jordbruk och den generella bedömningen är att insatserna bidrar till att uppfylla detta syfte. Det finns dock stor skillnad i hur effektiva insatserna är. Minskat kväveläckage anses ha en god kostnadseffektivitet, särskilt efter att ersättningsnivåerna anpassades under senare delen av programperioden. Även reduceringen av fosfor genom skyddszoner bedöms ha en högre kostnadseffektivitet jämfört med förra programperioden på grund av regionala skillnader i anslutning. När det gäller Extensiv vallodling visar utvärderingen stora regionala skillnader, och för andra insatser, såsom Restaurering och anläggning av våtmarker och Certifierad ekologisk odling, har det varit svårt att bedöma om de på ett kostnadseffektivt sätt bidragit till att uppfylla miljömålen.Miljöåtgärdernas effekter på miljömålet Giftfri miljö har inom ramen för dennautvärdering inte kunnat analyseras specifikt på grund av bristande underlag ochbegränsade resurser. Eftersom det generellt är svårt att utvärdera det specifika bidraget av de berörda ersättningarna till en giftfri miljö, kan utvärderingen därför inte på ett tillfredställande sätt svara på hur stor deras bidrag till detta miljökvalitetsmål har varit.När det gäller klimatåtgärder har programmet ett tydligt fokus på produktion ochanvändning av energi och relaterade emissioner av växthusgaser. Samtidigt konstateras det att emissionerna av växthusgaser från jordbrukssektorn primärt härrör från biogena processer i form av metan från idisslarnas matsmältning och lustgas från det kväve som tillförs åkermarken. För en fortsatt reduktion av jordbrukssektorns emissioner av växthusgaser bör satsningarna på en minskad användning av fossila bränslen fortsätta, men det är samtidigt nödvändigt att lägga ett större fokus på de biogena emissionerna. För att tydliggöra vikten av klimatåtgärder och satsningar på förnybar energi bör dessa insatser också lyftas fram som egna åtgärder istället för att finnas insprängda bland åtgärder som har annat huvudfokus.För ett fåtal åtgärder och ersättningar har det gått att härleda möjliga sysselsättningseffekter via de markanvändningseffekter som estimerats med modeller. Även om dessa resultat bör tolkas med stor försiktighet, bedöms sysselsättningseffekten av miljöåtgärderna generellt vara marginellt positiv. Ersättningen Skötsel av betesmarker och slåtterängar har i beräkningar som bygger på kontrafaktiska markanvändningsscenarier lett till en märkbar förändring av markanvändningen (ökad areal betesmarker med stöd) vilket, eftersom animalieproduktion generellt anses vara mer tidskrävande än spannmålsproduktion, bedöms leda till högre sysselsättning. Extensiv vallodling och kompensationsbidrag har däremot en mycket begränsad påverkanpå markanvändningen, varför sysselsättningseffekten bedöms som marginell.Generella förbättringsförslag inför utformningen av kommande programÄven om utvärderarnas samlade bedömning är att landsbygdsprogrammets upplägg, d.v.s. dess syften och motiv, ingående medel och val av åtgärder, är relevant och generellt bidrar till att förbättra situationen för miljö och klimat, så finns det en hel del som kan och bör förbättras för att möjliggöra kostnadseffektiva program i framtiden. De enstaka insatsernas syften och mål bör preciseras och kopplas till tydliga indikatorer som på ett relevant sätt kan mäta måluppfyllandet. Detta är avgörande för att man ska kunna utforma ett kostnadseffektivt landsbygdsprogram och utvärdera det på ett adekvat sätt. Dessutom behöver beskrivningarna för syften och motiv för många av ersättningarna ses över och anpassas till det aktuella kunskapsläget. Exempelvis skulle syftet ”bevara biologisk mångfald” leda till helt olika åtgärder beroende på om man vill bevara sällsynta arter eller ekosystemtjänstgynnare.Det empiriska underlaget för utvärdering behöver stärkas inför utvärderingen avframtida landsbygdsprogram. Detta kan exempelvis göras genom systematiskaöversikter och empirisk primärforskning som undersöker konsekvenser av olikaåtgärder. För att optimera detta bör utvärderingen byggas in som en organisk del av landsbygdsprogrammet. Utredarna föreslår att en procent av programmets budget används till att utforma och implementera relevanta metoder för kontinuerlig insamling av lämplig data under hela programperioden.För att i högre grad kunna utvärdera landsbygdsprogrammets kostnadseffektivitetkrävs en fortsatt utveckling av metoder för att studera konsekvenserna för målet av att åtgärden/insatsen/delinsatsen finns eller inte finns (eller var annorlunda utformad) (kontrafaktiska scenarier) och modeller som föruts
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3.
  • Stjernman, Martin, et al. (författare)
  • Habitat-specific bird trends and their effect on the Farmland Bird Index
  • 2013
  • Ingår i: Ecological Indicators. - : Elsevier BV. - 1872-7034 .- 1470-160X. ; 24, s. 382-391
  • Tidskriftsartikel (refereegranskat)abstract
    • Farmland birds in Europe have declined in numbers from the last decades, as reflected in the Farmland Bird Index (FBI), a multi-species indicator of population trends adopted by the European Union. Some of these farmland bird species breed to a varying degree also in non-farmland habitats: however, the indicator is calculated using trends estimated from all birds counted of each species, irrespective of habitat. Consequently, when interpreting indicators of farmland birds, it is important to know the influence of including the trends of the populations in non-farmland habitats. We estimated national and regional bird-habitat relationships and population trends of 14 of the species included in the Swedish version of FBI. Bird data came from the Swedish Bird Survey (1996-2008) including 716 separate routes, and detailed habitat data came from the Swedish Board of Agriculture (1999-2008). The proportion of individuals that occurred in non-farmland habitats ranged from 2% to 96%. Local densities were generally highest in farmland habitats, but because only 7-8% of the surface of Sweden is farmland, even low local densities in non-farmland sum up to high national totals. With few exceptions, the temporal trends of species were independent of the amount of farmland on routes, suggesting similar trends within and outside farmland. Accordingly, incorporating data on farmland birds from non-farmland habitats had only a limited effect on the FBI. But given that habitat-specific trends may well occur, it is important that multi-species indices are checked for potential habitat-specific differences among the included species. (C) 2012 Elsevier Ltd. All rights reserved.
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4.
  • Stjernman, Martin, et al. (författare)
  • Prognosverktyget Farmland Bird Index : tillämpning och vidareutveckling
  • 2014
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • Rapporten beskriver arbetet med att vidareutveckla och använda ett prognosverktyg för uppföljning och utvärdering av hur jordbrukspolitiken påverkar svenska jordbruksfåglar. Uppdraget gällde att dels utreda möjligheterna till förbättring av analysverktyget och rapporteringen av populationsutvecklingen för Sveriges jordbruksfåglar sammanfattad i Farmland Bird Index (FBI) samt att använda verktyget för att utvärdera effekter av miljöstöden för vall och bete samt kompensationsbidraget på FBI. Vi sammanfattar här de viktigaste resultaten av detta arbete.
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5.
  • Andersson, Georg, et al. (författare)
  • Effects of farming intensity, crop rotation and landscape heterogeneity on field bean pollination
  • 2014
  • Ingår i: Agriculture, Ecosystems & Environment. - : Elsevier BV. - 1873-2305 .- 0167-8809. ; 184, s. 145-148
  • Tidskriftsartikel (refereegranskat)abstract
    • Organic farming has the potential to enhance ecosystem services such as crop pollination. However, it is not known if a similar effect can be generated on conventional farms, without reducing external inputs such as inorganic fertilizers and pesticides, by using more complex crop rotations including ley for animal fodder production. In two separate designs, both located in southern Sweden, we tested if local organic farming and the landscape proportion of conventionally managed leys, along a landscape heterogeneity gradient, affected the pollination success of field bean. The number of developed pods was higher on organic farms compared to conventional ones. Development of beans, which demands high pollination efficiency, increased with increasing landscape heterogeneity, but only on organic farms. Increasing proportion of ley on conventional farms did not significantly influence the development of beans. The number of developed pods was not affected by the proportion of ley in the landscape. Our results demonstrate that in order to maximize pollination success it is important to improve both field management and preserve semi-natural habitats in the agricultural landscape. Reducing farming intensity with conventionally managed leys does not seem to be as effective as organic farming for delivering crop pollination services. (C) 2013 Elsevier B.V. All rights reserved.
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6.
  • Bensch, Staffan, et al. (författare)
  • Host specificity in avian blood parasites: a study of Plasmodium and Haemoproteus mitochondrial DNA amplified from birds
  • 2000
  • Ingår i: Royal Society of London. Proceedings B. Biological Sciences. - : The Royal Society. - 1471-2954. ; 267:1452, s. 1583-1589
  • Tidskriftsartikel (refereegranskat)abstract
    • A fragment of the mitochondrial cytochrome b gene of avian malaria (genera Haemoproteus and Plasmodium) was amplified from blood samples of 12 species of passerine birds from the genera Acrocephalus, Phylloscopus and Parus. By sequencing 478 nucleotides of the obtained fragments, we found 17 different mitocholdrial haplotypes of Haemoproteus or Plasmodium among the 12 bird species investigated. Only one out of the: 17 haplotypes was found in more than one host species, this exception being a haplotype detected in both blue tits (Parus caeruleus) and great tits (Parus major). The phylogenetic tree which was constructed grouped the sequences into two clades, most probably representing Haemoproteus and Plasmodium, respectively. We found two to four different parasite mitochondrial DNA (mtDNA) haplotypes in four bird species. The phylogenetic tree obtained from the mtDNA of the parasites matched the phylogenetic tree of the bird hosts poorly For example, the two tit species and the willow warbler (Phylloscopus troclilus) carried parasites differing by only 0.6% sequence divergence, suggesting that Haemoproteus shift both between species within the same genus and also between species in different families. Hence, host shifts seem to have occurred repeatedly in this parasite-host system. We discuss this in terms of the possilble evolutionary consequences for these bird species.
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7.
  • Birkhofer, Klaus, et al. (författare)
  • A framework to identify indicator species for ecosystem services in agricultural landscapes
  • 2018
  • Ingår i: Ecological Indicators. - : Elsevier BV. - 1470-160X .- 1872-7034. ; 91, s. 278-286
  • Tidskriftsartikel (refereegranskat)abstract
    • Improving our understanding of the relationships between biodiversity and the delivery of ecosystem services is crucial for the development of sustainable agriculture. We introduce a novel framework that is based on the identification of indicator species for single or multiple ecosystem services across taxonomic groups based on indicator species analyses. We utilize multi-species community data (unlike previous single species approaches) without giving up information about the identity of species in our framework (unlike previous species richness approaches). We compiled a comprehensive community dataset including abundances of 683 invertebrate, vertebrate and plant species to identify indicator species that were either positively or negatively related to biological control, diversity of red-listed species or crop yield in agricultural landscapes in southern Sweden. Our results demonstrate that some taxonomic groups include significantly higher percentages of indicator species for these ecosystem services. Spider communities for example included a higher percentage of significant positive indicator species for biological control than ground or rove beetle communities. Bundles of indicator species for the analysed ecosystem service potentials usually included species that could be linked to the respective ecosystem service based on their functional role in local communities. Several of these species are conspicuous enough to be monitored by trained amateurs and could be used in bundles that are either crucial for the provision of individual ecosystem services or indicate agricultural landscapes with high value for red-listed species or crop yields. The use of bundles of characteristic indicator species for the simultaneous assessment of ecosystem services may reduce the amount of labour, time and cost in future assessments. In addition, future analysis using our framework in other ecosystems or with other subsets of ecosystem services and taxonomic groups will improve our understanding of service-providing species in local communities. In any case, expert knowledge is needed to select species from the identified subsets of significant indicator species and these species should be validated by existing data or additional sampling prior to being used for ecosystem service monitoring.
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8.
  • Birkhofer, Klaus, et al. (författare)
  • Relationships between multiple biodiversity components and ecosystem services along a landscape complexity gradient
  • 2018
  • Ingår i: Biological Conservation. - : Elsevier BV. - 0006-3207 .- 1873-2917. ; 218, s. 247-253
  • Tidskriftsartikel (refereegranskat)abstract
    • The assessment of effects of anthropogenic disturbance on biodiversity (BD) and ecosystem services (ES) and their relationships are key priorities of the Intergovernmental Panel for Biodiversity and Ecosystem Services. Agricultural landscapes and their associated BD provide multiple ES and it is crucial to understand how relationships between ES and BD components change along gradients of landscape complexity. In this study, we related eight ES potentials to the species richness of five invertebrate, vertebrate and plant taxonomic groups in cereal farming systems. The landscape complexity gradient ranged from areas dominated by annually tilled arable land to areas with high proportions of unfertilized, non-rotational pastures and uncultivated field borders. We show that after accounting for landscape complexity relationships between yield and bird richness or biological control became more positive, but relationships between bird richness and biological control became less positive. The relationship between bird and plant richness turned from positive to negative. Multidiversity (overall biodiversity), was positively related to landscape complexity, whereas multifunctionality (overall ES provision), was not significantly related to either one of these. Our results suggest that multidiversity can be promoted by increasing landscape complexity; however; we found no support for a simultaneous increase of several individual ES, BD components or multifunctionality. These results challenge the assumption that bio-diversity-friendly landscape management will always simultaneously promote multiple ES in agricultural landscapes. Future studies need to verify this pattern by using multi-year data, larger sets of ES and BD components and a study design that is appropriate to address larger spatial scales and relationships in several regions.
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9.
  • Dänhardt, Juliana, et al. (författare)
  • Ekosystemtjänster i det skånska jordbrukslandskapet
  • 2013
  • Rapport (populärvet., debatt m.m.)abstract
    • Jordbrukslandskapet tillhandahåller ekosystemtjänster som utgör förutsättningen för en uthållig jordbruksproduktion och är till nytta för samhället i stort. Bakom dessa finns ekologiska processer som beror av samspel mellan en mångfald av organismer. Skånes jordbruk har genomgått betydande förändringar som förändrat landskapet och livsmiljön för många av dessa. För att bevara och förvalta ekosystemtjänsterna krävs en förståelse för sambanden mellan jordbruk, landskap och ekosystemprocesser. Rapporten beskriver ekologiska processer som ligger till grund för några viktiga ekosystemtjänster i Skånes jordbrukslandskap och visar betydelsen av biologisk mångfald för deras funktion. Där så är möjligt beskrivs hur de kan värderas. Slutligen redovisas praktiska åtgärder som gynnar dem. Rapporten visar att ekosystemtjänster inte enkelt går att ersätta med teknologiska lösningar, utan att förvaltning av dessa tjänster lönar sig. Detta kräver ökad ekologisk kunskap och anpassade styrmedel vilket kräver ökat samråd och regelbunden återkoppling mellan lantbrukare, myndigheter och forskare. Förhoppningen är att rapporten, framtagen av Lunds universitet och Region Skåne, inspirerar till detta!
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11.
  • Grindstaff, Jennifer, et al. (författare)
  • Transgenerational priming of immunity: maternal exposure to a bacterial antigen enhances offspring humoral immunity
  • 2006
  • Ingår i: Royal Society of London. Proceedings B. Biological Sciences. - : The Royal Society. - 1471-2954. ; 273:1600, s. 2551-2557
  • Tidskriftsartikel (refereegranskat)abstract
    • Young vertebrates have limited capacity to synthesize antibodies and are dependent on the protection of maternally transmitted antibodies for humoral disease resistance early in life. However, mothers may enhance fitness by priming their offspring's immune systems to elevate disease resistance. Transgenerational induced defences have been documented in plants and invertebrates, but maternal priming of offspring immunity in vertebrates has been essentially neglected. To test the ability of mothers to stimulate the immune systems of offspring, we manipulated maternal and offspring antigen exposure in a wild population of birds, pied flycatchers (Ficedula hypoleuca). We show that immunization of the mother before egg laying apparently stimulates a transgenerational defence against pathogens by elevating endogenous offspring antibody production. If the disease environments encountered by mothers and offspring are similar, this transgenerational immune priming may allow young to better cope with the local pathogen fauna.
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12.
  • Haslund, Knut Per, et al. (författare)
  • Bra vallersättning och kompensationsstöd? : Hur kan olika utformningar påverka jordbruket, miljön, och samhällsekonomin?
  • 2016
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • Positiva och negativa miljöeffekterVallersättningen och kompensationsstödet leder båda till att arealen vall och antalet nötkreatur ökar kraftigt. Utredningen konstaterar att effekten av vallodling på biologisk mångfald, både när det gäller sällsynta arter och ekosystemtjänster, är otillräckligt känd. Kompensationsstödet gör det företagsekonomiskt lönsamt att hävda betydligt större areal permanent betesmark, men vallersättningen leder däremot till något lägre betesareal.Det svenska jordbrukets kväve- och fosforläckage har varit lägre under de bådaanalyserade programperioderna tack vare vallersättningen. Under perioden 2015–20 är kväveläckaget är lägre än vad det skulle ha varit utan stödet också i slättbygderna, till skillnad från i landsbygdsprogrammets föregåendeperiod 2007–14. Kompensationsstödet medför tvärtom att växtnäringsläckagetär högre än vad det skulle vara om stödet inte fanns. Användningen av växtskyddsmedel i jordbruket påverkas inte mycket av dessa stöd under perioden 2015–20. Kompensationsstödet har under båda perioderna medfört stora utsläpp av växthusgaser. Vallersättningen är däremot bra ur klimatsynpunkt, om än inte lika starkt under perioden 2015–20 som under den föregående perioden. Stödens klimatpåverkan sker huvudsakligen genom att påverka mängden kol bundet i marken och antalet nötkreatur som avger växthusgasen metan, medan deras inverkan på jordbrukets användning av fossilbränsle till traktorer och annat är liten i sammanhanget. Kompensationsstödet är samhällsekonomiskt olönsamtVallersättningen medförde stora samhällsekonomiska förluster i början av perioden 2007–10, men efter ändrade stödregler och med högre världsmarknadspriser blev den i stället mycket lönsam. Även under innevarande programperiod 2015–20 har den en viss samhällsekonomisk lönsamhet. Kompensationsstödet ger dock stora samhällsekonomiska förluster, både under perioden 2007–14 och 2015–20. Samhällsekonomiskt sett vore det bra att halvera båda stöden. Kompensationsstödet ger många extra arbetstillfällen i områden med sämre förutsättningar för odling men till hög samhällsekonomisk kostnad. En del av kostnaden är att kompensationsstödet sammanvägt medför ökad miljöbelastning. Per budgetkrona var dock kostnaden relativt låg jämfört med andra arbetsmarknadspolitiska åtgärder. Störst betydelse för stödens samhällsekonomiska lönsamhet är deras klimateffekter, att deras skattefinansiering ger förluster i annan verksamhet, och att de leder till mindre effektiv jordbruksproduktion av marknadsvaror. Effekterna av stöden beror mycket på de ekonomiska förutsättningarna i övrigt, till exempel prisnivån för jordbruksprodukter på världsmarknaden. Utfallet kan bli ett annat än väntat om förutsättningarna ändras under perioden. Detta hände under perioden 2007–2014.
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13.
  • Herbertsson, Lina, et al. (författare)
  • The impact of sown flower strips on plant reproductive success in Southern Sweden varies with landscape context
  • 2018
  • Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809. ; 259, s. 127-134
  • Tidskriftsartikel (refereegranskat)abstract
    • In agricultural landscapes, sown flower strips can benefit pollinators and pollination of nearby plants, but their impact on pollination in the wider landscape is poorly studied. We evaluated effects on reproductive success of field bean (Vicia faba) and woodland strawberry (Fragaria vesca) using data from two study systems, both including study sites (1 km radius) with (flower strip sites) or without flower strips (control sites). To assess whether flower strips enhance pollination in the wider landscape, we compared the reproductive success between plants growing in field borders (> 160 m to nearest flower strip) at flower strips sites and control sites. We also tested if flower strips reallocate pollination functions in the landscape. We did this by comparing the reproductive success of plants at flower strip sites, growing adjacent to the flower strips with plants growing in a more distant field border at the same site (> 160 m). Finally, we tested if these potential effects depended on the heterogeneity of the landscape. In field borders without an adjacent flower strip, plant reproductive success was unaffected by the presence of a flower strip at the site, and increased with increasing landscape heterogeneity independently of site type (flower strip vs. control). In contrast, adjacent to the flower strips, reproductive success declined with increasing landscape heterogeneity, resulting in a positive net effect of adjacent flower strips in homogeneous landscapes and a negative effect in heterogeneous landscapes. Our results show that while decreasing landscape heterogeneity may impair pollination in homogeneous landscapes, this can be locally mitigated by sowing flower strips. However, in heterogeneous landscapes, flower strips may instead reduce pollination of adjacent plants.
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14.
  • Hristov, Jordan, et al. (författare)
  • Impacts of the EU's Common Agricultural Policy “Greening” Reform on Agricultural Development, Biodiversity, and Ecosystem Services
  • 2020
  • Ingår i: Applied Economic Perspectives and Policy. - : Wiley. - 2040-5790 .- 2040-5804. ; 42:4, s. 716-738
  • Tidskriftsartikel (refereegranskat)abstract
    • The EU's Common Agricultural Policy (CAP) has had limited success in mitigating agriculture's environmental degradation. In this paper we simulate the impacts of the 2013 “greening” reform on biodiversity and ecosystem services in environmentally contrasting landscapes. We do this by integrating an agent-based model of structural change with spatial ecological production functions, and show that the reform will likely fail to deliver substantial environmental benefits. Our study implies that greening measures need to be tailored to local conditions and priorities, to generate environmental improvements. Such spatial targeting of measures is though incompatible with the design of a common direct payments scheme.
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15.
  • Lindström, Åke, et al. (författare)
  • What measures should be taken to improve conditions for Swedish Farmland Birds, as reflected in the Farmland Bird Index?
  • 2017
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • Many birds species connected to the agricultural landscape have for several decades fared poorly in Sweden, as well as in Europe as a whole. This is reflected in the decline of the Farmland Bird Index, an official EU indicator for farmland birds specifically, and biodiversity in general. The Swedish Board of Agriculture invited us to propose measures that will improve the conditions for farmland birds in Sweden.In this report, we have briefly summarized the scientific literature on potential drivers of farmland bird numbers, analysed temporal trends in farmland birds and some farming practices, and modelled the spatial distribution of farmland birds in relation to farming practices. The bird data come from the Swedish Breeding Bird Survey, and the farming practise data from the Swedish Land Parcel Information System (Swedish Board of Agriculture). Based on our findings, we propose a suit of measures concerning the quantity and quality of farmland that would improve the future conditions for farmland birds. At the more general level, farmland birds would benefit if the ongoing loss of farmland in general and important semi-natural habitats in particular was halted. We also propose that farmland birds would benefit from measures taken to promote mixed farming (combined animal husbandry and crop production at the same farms), notably to increase crop farming in the north and animal husbandry on the plains. Increased use of set-asides of various kind, not least those of varied vegetation structure and year-round cover, would also benefit farmland birds. Furthermore, farmland birds would most likely also benefit from more wetlands in the Agricultural landscape, reduced use of pesticides and inorganic fertilizers, and more spring-sown crops. They may benefit from higher crop diversity at the farm level, and we found some evidence for this. Some more directed measures may also benefit the Farmland Bird Index; we found support for the benefits of wild bird cover (“fågelåkrar”), skylark plots (“lärkrutor”), buffer strips (“skyddszoner”) and appropriately managed ecological focus areas (“ekologiska fokusområden”).
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16.
  • Marinovic, Tomislav, 1991, et al. (författare)
  • Fast Characterization of Mutually Coupled Array Antennas Using Isolated Antenna Far-Field Data
  • 2021
  • Ingår i: IEEE Transactions on Antennas and Propagation. - 0018-926X .- 1558-2221. ; 69:1, s. 206-218
  • Tidskriftsartikel (refereegranskat)abstract
    • A new method is proposed to analyze antenna arrays including mutual coupling, which is based on the concept of multiple scattering and relates to the iterative Jacobi and Gauss-Seidel methods. The method employs sampled far-field data of an isolated element, which can be obtained by any full-wave simulator and consists of far fields for excitation at the antenna feed and for plane waves with different angles of incidence. Mutual interactions between the array elements are modeled by approximating the incident field as a single dual-polarized plane wave taken from the spherical wave expansion of the scattered field from any other element in the array. The accuracy and run-time performances of the method are evaluated mainly by comparing simulations for several array geometries to MoM-based full-wave solutions. The method is primarily intended as a tool for the fast sequential analysis of arrays while varying the array lattice, particularly in case of irregular or sparse lattices and complex elements requiring dense meshes in full-wave simulators. The applications of the method may thus range from the systematic analysis of mutual coupling to optimization and synthesis.
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17.
  • Nilsson, Johan, et al. (författare)
  • Experimental reduction of incubation temperature affects both nestling and adult blue tits Cyanistes caeruleus
  • 2008
  • Ingår i: Journal of Avian Biology. - 0908-8857. ; 39:5, s. 553-559
  • Tidskriftsartikel (refereegranskat)abstract
    • Incubation was for a long time considered to be a period of decreased activity and low cost for parents. It was therefore ignored as a potential factor affecting life-history trade-offs in birds. Lately this view has started to change, and studies now show that there might be considerable costs connected to incubation. We experimentally reduced the nest temperature during incubation in blue tits Cyanistes caeruleus, thus increasing the energetic cost of incubation, to test the importance of incubation as a component of reproductive costs and for nestling quality. While most other studies use brood size manipulation to manipulate reproductive costs, we were able to separate treatment effects acting during the incubation period from those acting on later reproductive performance by applying a cross-foster design. We were also able to isolate the effects of decreased incubation temperature on the nestlings from treatment effects acting on incubating females. We found no experimental effect on the length of the incubation period or on hatching success. The lower temperature during incubation, however, caused lower growth rates in nestlings and reduced chick rearing capacity in adults. We conclude that incubation is a costly period, with the potential to affect both the trade-off between current and future reproduction and the one between parental effort and offspring quality within the current breeding attempt.
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18.
  • Olsson, Ola, et al. (författare)
  • Efficient, automated and robust pollen analysis using deep learning
  • 2021
  • Ingår i: Methods in Ecology and Evolution. - 2041-210X. ; 12:5, s. 850-862
  • Tidskriftsartikel (refereegranskat)abstract
    • Pollen analysis is an important tool in many fields, including pollination ecology, paleoclimatology, paleoecology, honey quality control, and even medicine and forensics. However, labour‐intensive manual pollen analysis often constrains the number of samples processed or the number of pollen analysed per sample. Thus, there is a desire to develop reliable, high‐throughput, automated systems. We present an automated method for pollen analysis, based on deep learning convolutional neural networks (CNN). We scanned microscope slides with fuchsine stained, fresh pollen and automatically extracted images of all individual pollen grains. CNN models were trained on reference samples (122,000 pollen grains, from 347 flowers of 83 species of 17 families). The models were used to classify images of different pollen grains in a series of experiments. We also propose an adjustment to reduce overestimation of sample diversity in cases where samples are likely to contain few species. Accuracy of a model for 83 species was 0.98 when all samples of each species were first pooled, and then split into a training and a validation set (splitting experiment). However, accuracy was much lower (0.41) when individual reference samples from different flowers were kept separate, and one such sample was used for validation of models trained on remaining samples of the species (leave‐one‐out experiment). We therefore combined species into 28 pollen types where a new leave‐one‐out experiment revealed an overall accuracy of 0.68, and recall rates >0.90 in most pollen types. When validating against 63,650 manually identified pollen grains from 370 bumblebee samples, we obtained an accuracy of 0.79, but our adjustment procedure increased this to 0.85. Validation through splitting experiments may overestimate robustness of CNN pollen analysis in new contexts (samples). Nevertheless, our method has the potential to allow large quantities of real pollen data to be analysed with reasonable accuracy. Although compiling pollen reference libraries is time‐consuming, this is simplified by our method, and can lead to widely accessible and shareable resources for pollen analysis.
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19.
  • Olsson, Ola, et al. (författare)
  • Optimizing Species Richness in Mosaic Landscapes : A Probabilistic Model of Species-Area Relationships
  • 2021
  • Ingår i: Frontiers in Conservation Science. - : Frontiers Media SA. - 2673-611X. ; 2
  • Tidskriftsartikel (refereegranskat)abstract
    • Most landscapes are comprised of multiple habitat types differing in the biodiversity they contain. This is certainly true for human modified landscapes, which are often a mix of habitats managed with different intensity, semi-natural habitats and even pristine habitats. To understand fundamental questions of how the composition of such landscapes affects biodiversity conservation, and to evaluate biodiversity consequences of policies that affect the composition of landscapes, there is a need for models able to translate information on biodiversity from individual habitats to landscape-wide predictions. However, this is complicated by species richness not being additive. We constructed a model to help analyze and solve this problem based on two simple assumptions. Firstly, that a habitat can be characterized by the biological community inhabiting it; i.e., which species occur and at what densities. Secondly, that the probability of a species occurring in a particular unit of land is dictated by its average density in the associated habitats, its spatial aggregation, and the size of the land unit. This model leads to a multidimensional species-area relation (one dimension per habitat). If the goal is to maximize species diversity at the landscape scale (γ-diversity), within a fixed area or under a limited budget, the model can be used to find the optimal allocation of the different habitats. In general, the optimal solution depends on the total size of the species pool of the different habitats, but also their similarity (β-diversity). If habitats are complementary (high β), a mix is usually preferred, even if one habitat is poorer (lower α diversity in one habitat). The model lends itself to economic analyses of biodiversity problems, without the need to monetarize biodiversity value, i.e., cost-effectiveness analysis. Land prices and management costs will affect the solution, such that the model can be used to estimate the number of species gained in relation to expenditure on each habitat. We illustrate the utility of the model by applying it to agricultural landscapes in southern Sweden and demonstrate how empirical monitoring data can be used to find the best habitat allocation for biodiversity conservation within and between landscapes.
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20.
  • Post, Maria von, et al. (författare)
  • Effects of supplemental winter feeding on House Sparrows (Passer domesticus) in relation to landscape structure and farming systems in southern Sweden
  • 2013
  • Ingår i: Bird Study. - : Informa UK Limited. - 0006-3657 .- 1944-6705. ; 60:2, s. 238-246
  • Tidskriftsartikel (refereegranskat)abstract
    • CapsuleHouse Sparrow (Passer domesticus) populations in south Swedish farmland are not affected by supplemental winter feeding, irrespective of agricultural landscape type or presence of animal husbandry, although winter populations declined more in mixed farmland and when farms contained animal husbandry. AimsTo investigate whether food limitation of House Sparrow population size during the winter varied spatially in relation to agricultural landscape intensification and farm management. MethodsWe experimentally increased the winter food supply for populations on farmsteads in replicated landscapes that differed in agricultural intensification (open plains versus mixed farming) and/or farm management (crop farming versus animal husbandry), and estimated possible differences in effects on winter population change. ResultsWe found no effect of supplementary winter feeding on changes in House Sparrow population sizes over the winter, irrespective of agricultural landscape type or presence of animal husbandry at the farm. However, we found a significantly larger winter population decline in mixed farmland and when farms contained animal husbandry. ConclusionsThe results suggest that House Sparrow populations in south Swedish farmland are not primarily limited by winter food availability. Alternatively, supplemental winter feeding may augment interspecific competition or attracts predators, offsetting any positive effect on population change. However, the stronger population decline in landscapes in which more breeding resources may be available (animal husbandry farms, mixed farmland), suggests stronger intraspecific competition during the winter in line with the resource separation hypothesis.
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21.
  • Rader, Romina, et al. (författare)
  • Organic farming and heterogeneous landscapes positively affect different measures of plant diversity
  • 2014
  • Ingår i: Journal of Applied Ecology. - : Wiley. - 0021-8901 .- 1365-2664. ; 51:6, s. 1544-1553
  • Tidskriftsartikel (refereegranskat)abstract
    • Increasing landscape heterogeneity and organic farming practices are known to enhance species richness in agroecosystems. However, little is known about the consequences of these management options on other biodiversity components such as community composition, phylogenetic structure and functional diversity which may be more closely linked to ecosystem functioning. We surveyed semi-natural plant communities within the uncultivated field margins of 18 arable farms in Skane, south Sweden. We investigated how taxonomic, phylogenetic and functional diversity responds to landscape heterogeneity (presence of semi-natural habitat) and farm management intensity (organic vs. conventional farming). Plant species richness and functional diversity metrics all responded positively to landscape heterogeneity, with the strongest effect occurring on conventional farms. Community composition differed with farm management, and mean phylogenetic relatedness, an indicator of phylogenetic structure, was significantly higher on the field margins of organic compared to conventional farms. Individual plant functional groups themselves responded in unique ways to land management and landscape heterogeneity.Synthesis and applications. Management strategies that promote the conservation of heterogeneous landscapes (i.e. a higher proportion of semi-natural habitats) and organic farm management practices are important for maintaining plant phylogenetic, functional and taxonomic diversity in agroecosystems. Accommodating various forms of diversity is important to ensure that ecosystems have the greatest possible array of species ecologies'. Such measures will help to improve the capacity of these ecosystems to provide multiple ecosystem functions, including the sustaining and regulating services of benefit to people. Management strategies that promote the conservation of heterogeneous landscapes (i.e. a higher proportion of semi-natural habitats) and organic farm management practices are important for maintaining plant phylogenetic, functional and taxonomic diversity in agroecosystems. Accommodating various forms of diversity is important to ensure that ecosystems have the greatest possible array of species ecologies'. Such measures will help to improve the capacity of these ecosystems to provide multiple ecosystem functions, including the sustaining and regulating services of benefit to people.
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22.
  • Russell, James C., et al. (författare)
  • Community occupancy before-after-control-impact (CO-BACI) analysis of Hurricane Gudrun on Swedish forest birds
  • 2015
  • Ingår i: Ecological Applications. - : Wiley. - 1051-0761. ; 25:3, s. 685-694
  • Tidskriftsartikel (refereegranskat)abstract
    • Resilience of ecological communities to perturbation is important in the face of increased global change from anthropogenic stressors. Monitoring is required to detect the impact of, and recovery from, perturbations, and before-after-control-impact (BACI) analysis provides a powerful framework in this regard. However, species in a community are not observed with perfect detection, and occupancy analysis is required to correct for imperfect detectability of species. We present a Bayesian community occupancy before-after-control-impact (CO-BACI) framework to monitor ecological community response to perturbation when constituent species are imperfectly detected. We test the power of the model to detect changes in community composition following an acute perturbation with simulation. We then apply the model to a study of the impact of a large hurricane on the forest bird community of Sweden, using data from the national bird survey scheme. Although simulation shows the model can detect changes in community occupancy following an acute perturbation, application to a Swedish forest bird community following a major hurricane detected no change in community occupancy despite widespread forest loss. Birds with landscape occupancy less than 50% required correcting for detectability. We conclude that CO-BACI analysis is a useful tool that can incorporate rare species in analyses and detect occupancy changes in ecological communities following perturbation, but, because it does not include abundance, some impacts may be overlooked.
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23.
  • Råberg, Lars, et al. (författare)
  • Immune responsiveness in adult blue tits: heritability and effects of nutritional status during ontogeny
  • 2003
  • Ingår i: Oecologia. - : Springer Science and Business Media LLC. - 1432-1939 .- 0029-8549. ; 136:3, s. 360-364
  • Tidskriftsartikel (refereegranskat)abstract
    • What is the relative contribution of genetic and various environmental factors to variation in the ability to mount an immune response? We measured antibody responsiveness to diphtheria-tetanus vaccine during the winter in free-ranging blue tits with a known nestling history to investigate (1) if nutritional status during the nestling stage has persistent effects on an individual's immune defence and (2) if immune responsiveness is heritable. There was no correlation between nutritional status during the nestling phase (measured as size-corrected body mass day 14 post-hatch) and antibody responsiveness as an adult. On the other hand, the heritability of responsiveness to diphtheria and tetanus, as estimated by parent-offspring regression, was 0.21+/-0.51 and 1.21+/-0.40 SE, respectively. Thus, while there was little evidence that natural variation in antibody responsiveness to these antigens reflected nutritional conditions during early life, responsiveness to at least one of the antigens (tetanus) had a strong genetic component.
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24.
  • Råberg, Lars, et al. (författare)
  • Natural selection on immune responsiveness in blue tits Parus caeruleus
  • 2003
  • Ingår i: Evolution. - 1558-5646. ; 57:7, s. 1670-1678
  • Tidskriftsartikel (refereegranskat)abstract
    • What is the form of natural selection on immune responsiveness? For a population at evolutionary equilibrium, there are two different scenarios. First, it is generally assumed that immune defense has both benefits and costs. If variation in immune responsiveness is due to variation in how individuals trade off these costs and benefits, one would expect immune responsiveness to be subject to stabilizing selection. Second, it is well known that an individual's immune responsiveness is often dependent on its overall condition. If immune responsiveness is condition-dependent, one would expect immune responsiveness to be under positive directional selection. We would therefore expect that the form of natural selection on immune responsiveness depends on the relative magnitude of these two sources of variation: variation in how individuals trade off the costs and benefits of defense, and variation in condition. We measured primary and secondary antibody responsiveness to diphtheria-tetanus vaccine in blue tits during winter and investigated the relationship between responsiveness and survival to the following breeding season. We use responsiveness to these antigens as measures of an individual's ability or propensity to mount an antibody response in case of an infection. Interestingly, different measures of responsiveness were subject to different selective regimes: primary responsiveness to diphtheria was subject to stabilizing selection, whereas secondary responsiveness to tetanus was subject to positive directional selection. In contrast, there was no significant selection on primary responsiveness to tetanus or secondary responsiveness to diphtheria. The finding of stabilizing selection on a measure of responsiveness is evidence that immune defense can incur fitness costs; a central but little-tested assumption of theories of the ecology and evolution of immunological defense. The finding of directional selection on a measure of responsiveness is consistent with the idea that immune responsiveness is condition-dependent, although we cannot rule out the alternative explanation that the population is not at evolutionary equilibrium with respect to this trait.
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25.
  • Råberg, Lars, et al. (författare)
  • Sex and environmental sensitivity in blue tit nestlings
  • 2005
  • Ingår i: Oecologia. - : Springer Science and Business Media LLC. - 1432-1939 .- 0029-8549. ; 145:3, s. 496-503
  • Tidskriftsartikel (refereegranskat)abstract
    • In birds and mammals with sexual size dimorphism (SSD), the larger sex is typically more sensitive to adverse environmental conditions, such as food shortage, during ontogeny. However, some recent studies of altricial birds have found that the larger sex is less sensitive, apparently because large size renders an advantage in sibling competition. Still, this effect is not an inevitable outcome of sibling competition, because several studies of other species of altricial birds have found the traditional pattern. We investigated if the sexes differ in environmental sensitivity during ontogeny in the blue tit, a small altricial bird with c. 6% SSD in body mass (males larger than females). We performed a cross-fostering and brood size manipulation experiment during 2 years to investigate if the sexes were differently affected as regards body size (body mass, tarsus and wing length on day 14 after hatching) and pre-fledging survival. We also investigated if the relationship between body size and post-fledging survival differed between the sexes. Pre-fledging mortality was higher in enlarged than in reduced broods, representing poor and good environments, respectively, but the brood size manipulation did not affect the mortality rate of males and females differently. In both years, both males and females were smaller on day 14 after hatching in enlarged as compared to reduced broods. In one of the years, we also found significant Sex x Experiment interactions for body size, such that females were more affected by poor environmental conditions than that of males. Body size was positively correlated with post-fledging survival, but we found no interactive effects of sex and morphological traits on survival. We conclude that in the blue tit, females (the smaller sex) are more sensitive to adverse environmental conditions which, in our study, was manifest in terms of fledgling size. A review of published studies of sex differences in environmental sensitivity in sexually size-dimorphic altricial birds suggests that the smaller sex is more sensitive than the larger sex in species with large brood size and vice versa.
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26.
  • Råberg, Lars, et al. (författare)
  • The cost of an immune response: vaccination reduces parental effort
  • 2000
  • Ingår i: Ecology Letters. - : Wiley. - 1461-023X .- 1461-0248. ; 3:5, s. 382-386
  • Tidskriftsartikel (refereegranskat)abstract
    • A fundamental assumption of theories of the ecology and evolution of inducible defences is that protective responses to attacks by parasites or predators should not only have benefits, but also costs. The vertebrate immune system is by far the best studied example of an inducible defence, yet little is known about the costs of an immune response, especially in natural populations. To test: if an immune response per se is costly, we induced an antibody response in female blue tits, Parus caeruleus, by immunising them with human diphtheria-tetanus vaccine, and compared their nestling-feeding rate with that of saline-injected controls. We found that vaccinated females reduced their nestling feeding rate, thus demonstrating a cost of the immune response in the currency of parental effort.
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27.
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28.
  • Sahrbacher, Christoph, et al. (författare)
  • Modelling spatial relationships between ecosystem services and agricultural production in an agent-based model
  • 2014
  • Ingår i: ; , s. 1311-1318
  • Konferensbidrag (refereegranskat)abstract
    • The collective impacts of farmers' land management decisions on above ground ecosystem services (ES) and their implications for agriculture are poorly understood. Managing habitat to provide ES is costly but at the same time it can support higher yields through, e.g., pollination or natural pest control. Due to the mobility of ES-providers (bees, natural enemies) farmers providing habitat might also benefit their neighbours, creating interdependencies among their decisions. Interdependencies among farmers' land-use decisions and the flow of ES in space can be considered by integrating agent-based modelling and evidence-based ES models. Such integration requires a trade-off between the land-use details required to capture relevant ecological dynamics of ES in a landscape and the simplified landscape modelling in agent-based models. This paper shows how details of land use can be increased in the agent-based model AgriPoliS that simulates agricultural structural change. Non-agricultural land in AgriPoliS is differentiated into different land uses, i.e. settlements and natural habitats. Furthermore, the size distribution of these landscape elements and their distribution in space are considered. The improvement of the landscape modelling is a prerequisite for detailed analysis of policies supporting biodiversity and their impact on agricultural production and farm income.
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29.
  • Stjernman, Martin, et al. (författare)
  • Biologisk mångfald och betydelsen av skyddade områden : Utvärdering och indikatorer i ett landskapsperspektiv
  • 2023
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • Trots att ytan av formellt skyddade områden ökar så minskar den biologiska mångfalden i Sverige. För att naturvården i Sverige ska bli effektivare krävs det ökad kunskap om varför områdesskyddet inte räcker till för att bevara den biologiska mångfalden. En effektiv naturvård kräver kunskap om vilken effekt områdesskydd har på den biolo­giska mångfalden. Eftersom biologisk mångfald påverkas av ekologiska processer på skalor som kan vara större än enskilda reservat, tar vi i denna rapport upp hur skyddade områden bör följas upp i ett landskapsperspektiv. Ett sådant perspektiv behandlar var skyddade områden placeras i landskapet och hur landskapet runt skyddade områden hanteras för att bevara mångfalden. Som grund för detta beskriver vi hur uppföljningen av områdesskydd i Sverige bedrivs idag, vilka aspekter som bör vägas in när man utvär­derar områdesskydd, och indikatorer som idag används för att följa upp områdesskydd. Utifrån detta ger vi ett antal rekommendationer om framtida uppföljningar. Vi beskriver relevanta ekologiska teorier för hur organismers rörelser inom genera­tioner (dagliga eller säsongsmässiga rörelser) och mellan generationer (spridning) inne­bär att både risken för utrotning och lokala populationsstorlekar beror av det omgivande landskapets karaktär. I vissa fall leder dessa processer till tidsfördröjda effekter, vilket gör att det inte räcker att följa den biologiska mångfalden som sådan, utan även hur landskapets struktur utvecklas, för att hinna reagera på förändringar i tid. Relevanta ekologiska teorier kan användas för att förstå hur landskapets komposition (mängd habitat) och dess konfiguration (hur habitat är fördelat) påverkar organismer i ett skyd­dat område, men detta kräver ökade kunskaper om hur organismer utnyttjar resurser över olika skalor och sprider sig mellan delpopulationer. En systematisk kunskapssammanställning visar att ekologiska processer på landskapsskalor påverkar popula­tioner i skyddade områden, men att det empiriska underlaget är svagt och inte tillåter analyser av vilka ekologiska processer som har störst betydelse på landskapsnivå. Även vad gäller naturliga störningar behövs ett landskapsperspektiv. Eftersom regelbundna störningar kan vara svåra att säkerställa i tillräcklig omfattning i enskilda reservat krävs ett fokus på att säkerställa förekomst av störningar i hela landskap. Även här är det empiriska underlaget svagt. I en internationell utblick går vi igenom vilka indikatorer som kan användas för att följa upp biologisk mångfald, baserat på inventeringar, habitatkaraktärisering och expertbedömningar. Vi gör också en genomgång av uppföljning och övervakning av bio­logisk mångfald i Sverige idag, både generellt och med avseende på skyddade områden. Det nuvarande systemet med uppföljning av typiska arter skulle kunna utvecklas till ett indikatorsystem, genom att arter grupperas efter olika habitatkrav och rörlighet, för att fungera som indikatorer eller informera modellbaserade indikatorer. Den nuvarande hanteringen av data försvårar dock utnyttjandet av data för uppföljning. Vi beskriver hur data kan informera indikatorer som sedan kan användas för att informera beslut. Genom att kombinera befintliga generella övervakningsprogram, specifika invente­ringar och fjärranalys, kan både specifika och generella bevarandemål följas upp genom statistisk analys och processbaserad modellering. Vi sätter indikatorer i ett utvärderings­sammanhang genom att utgå ifrån Förändringsteori (Theory of Change) vilken bildar grunden för ett ramverk för utvärdering av skyddade områden kallat PAME (Protected Area Management Effectiveness). Där används en process för programutvärdering som utifrån definierade mål och medel (i det här fallet bevarande av biologisk mångfald genom områdesskydd), beskriver vägen från åtgärd till resultat i flera steg i en så kallad effektkedja. En slutsats av detta perspektiv är att dagens utvärderingar oftast saknar en kontrafaktisk analys, det vill säga en jämförelse mellan vad som hänt med och utan skydd, vilket försvårar slutsatser om områdesskyddets betydelse. Möjlighe­ten att göra sådana analyser försvåras också av att data inte systematiskt samlas in både i och utanför skyddade områden, vilket gör det svårt att jämföra vad som händer i skyddade och icke-skyddade områden som kan skilja sig på andra sätt än i skyddet som sådant.  Utifrån våra analyser drar vi slutsatsen att dagens uppföljningar behöver bli bättre på att fånga effekten av områdesskydd som sådant och att utvärderingar av områdes­skydd ofta saknar ett landskapsperspektiv. Vi menar dock att en kombination av stärkt datainsamling, bättre utnyttjande av fjärranalys, samt strukturerad uppföljning och analys med dessa data enligt Förändringsteori, utgör en bra grund för vetenskapligt grundade utvärderingar av skyddets verkliga betydelse för biologisk mångfald. Vi rekommenderar att sådana analyser är kontrafaktiska och fokuserar både på specifika och allmänna värden för biologisk mångfald. Detta kräver förstärkt insamling och nyttjande av data, både från skyddade och icke-skyddade områden. Analyser bör använda sig av ett explicit landskapsperspektiv, vilket kommer att kräva att en bred palett av metoder används, anpassad till kunskapen om enskilda organismer och deras sätt att använda landskap. Det är lämpligt att anta en strategi för hantering av varierande kunskapsunderlag inom vilken val av metod för att svara på en utvärde­ringsfråga kan anpassas till den kombination av information som är tillgänglig vid utvärderingstillfället. En uttrycklig hantering av osäkerhet kombinerad med försiktig­hetsprinciper, säkerställer att brist på kunskap inte leder till beslut som äventyrar den biologiska mångfalden.
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30.
  • Stjernman, Martin (författare)
  • Causes and consequences of blood parasite infections in birds
  • 2004
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Parasites are ubiquitous and can cause significant fitness reductions to their hosts. Therefore, selection for the evolution of host resistance should be strong. However, resistance may be costly and should be traded-off against other fitness related traits. Parasites could therefore have a significant impact on the evolution of fitness related characters of their hosts. It has been suggested that the workload put into reproduction is negatively related to the ability to resist parasites and that this trade-off could explain the reduction in future reproduction as a result of current reproductive effort – a trade-off termed the cost of reproduction. I studied whether blood parasites could mediate reproductive costs by examining if altered reproductive effort affected infection levels of a blood parasite (Haemoproteus) and concomitant survival in the blue tit (Parus caeruleus). I found a negative relationship between altered reproductive effort and survival and a positive relationship between reproductive effort and parasite intensity. However, since parasite intensities were not related to survival when controlling for other factors related to the experiment, these parasites could not mediate the reproductive costs found. An alternative way of verifying costs of resistance may be to study selection patterns since the presence of such fitness costs should manifest as stabilising selection on resistance. That is, fitness is not only reduced if hosts are unable to control the parasites, but also if resistance comes with a fitness cost. Indeed, I found that individuals with intermediate parasite intensities had highest survival. I also found that individuals with intermediate immune responsiveness against diphtheria vaccine had highest survival. However, different components of resistance may carry different costs since I found that individuals with the strongest response against another antigen (tetanus) were those that had highest survival. Another finding was that the intensity of infection within one-year-old individuals were significantly related to the rearing conditions experienced during the nestling phase and that the level of infection is repeatable between years. This suggests that parasite resistance is fixed during development and that individuals have limited possibilities to compensate for adverse conditions experienced during the nestling phase. The influence of early development on parasite resistance indicate that maternal effects may be important and one possible route by which the mother could influence offspring immunity may be through the transfer of antibodies via the egg. I found that offspring of mothers that were immunised with a bacterial antigen had higher levels of (and a larger increase in) antibodies at the end of the nestling period compared to offspring of mothers that were not immunised.
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31.
  • Stjernman, Martin, et al. (författare)
  • Estimating effects of arable land use intensity on farmland birds using joint species modeling
  • 2019
  • Ingår i: Ecological Applications. - : Wiley. - 1051-0761 .- 1939-5582. ; 29:4
  • Tidskriftsartikel (refereegranskat)abstract
    • Declines in European farmland birds over past decades have been attributed to the combined effects of agricultural intensification and abandonment. Consequently, aspirations to stop declines should focus attention on reversing these changes through voluntary or policy-driven interventions. The design of such interventions should ideally be informed by scientific knowledge of which aspects of the transformation of agricultural landscapes have contributed to the farmland bird declines. Declines may be associated with loss of natural habitats or the intensification and homogenization of land use management on production land, and furthermore, these changes may interact. Here, we applied an orthogonal design exploiting spatial variation in land use in a major agricultural region of Sweden to seek evidence for benefits to farmland birds of reversing some of the intensifications on and among arable fields and whether effects are modified by the availability of seminatural habitats (pastures and field borders) in the landscape. We accounted for the potentially confounding effect of interactions between species by using a joint species distribution model explicitly controlling for additional variation and covariation among species. We found that interventions aimed specifically at land in production could provide benefits to farmland birds. Landscapes with a higher proportion leys or fallows and/or with a more diverse set of crops held higher abundances of most farmland birds. However, effects were only apparent in landscapes with low availability of seminatural habitats and were sometimes even negative in landscapes with high amounts of such habitats, demonstrating context dependence. Even if we found little evidence of interactions between species, the joint modeling approach provided several benefits. It allowed information to be shared between species making analyses robust to uncertainty due to low abundances and provided direct information about the mean and variability in effects of studied predictors among species. We also found that care needs to be taken regarding prior and distributional assumptions as the importance of species interactions might otherwise be overstated. We conclude that this approach is well suited for evaluating agricultural policies by providing evidence for or against certain interventions or to be linked to policy scenarios of land use change.
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32.
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33.
  • Stjernman, Martin, et al. (författare)
  • Long-term effects of nestling condition on blood parasite resistance in blue tits (Cyanistes caeruleus).
  • 2008
  • Ingår i: Canadian Journal of Zoology. - 1480-3283. ; 86:9, s. 937-946
  • Tidskriftsartikel (refereegranskat)abstract
    • Little is know about whether the conditions experienced during ontogeny affect resistance to parasites later in life in wild animals. Here, we used a population of blue tits (Cyanistes caeruleus (L., 1758)) to investigate to what extent conditions experienced during the nestling stage could explain the ability to control blood parasite (Haemoproteus majoris (Laveran, 1902)) infections 1 year later. Although short-term effects may be expected based on the well-known sensitivity of the immune system to current conditions, it is less known whether this translates into a permanent alteration of parasite resistance. By relating nestling condition (measured as body mass or size-corrected body mass) at the beginning and end of the nestling stage to parasite intensity of individual recruiting birds 1 year later, we indeed found significant positive effects of both early and late nestling condition on the long-term ability to control parasites. These results indicate that parasites may be important as a mechanistic explanation for the trade-off between number and quality of offspring. It further points to the potential relevance for maternal effects in host–parasite interactions.
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34.
  • Stjernman, Martin, et al. (författare)
  • Maximum host survival at intermediate parasite infection intensities.
  • 2008
  • Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 3:6
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Although parasitism has been acknowledged as an important selective force in the evolution of host life histories, studies of fitness effects of parasites in wild populations have yielded mixed results. One reason for this may be that most studies only test for a linear relationship between infection intensity and host fitness. If resistance to parasites is costly, however, fitness may be reduced both for hosts with low infection intensities (cost of resistance) and high infection intensities (cost of parasitism), such that individuals with intermediate infection intensities have highest fitness. Under this scenario one would expect a non-linear relationship between infection intensity and fitness. METHODOLOGY/PRINCIPAL FINDINGS: Using data from blue tits (Cyanistes caeruleus) in southern Sweden, we investigated the relationship between the intensity of infection of its blood parasite (Haemoproteus majoris) and host survival to the following winter. Presence and intensity of parasite infections were determined by microscopy and confirmed using PCR of a 480 bp section of the cytochrome-b-gene. While a linear model suggested no relationship between parasite intensity and survival (F = 0.01, p = 0.94), a non-linear model showed a significant negative quadratic effect (quadratic parasite intensity: F = 4.65, p = 0.032; linear parasite intensity F = 4.47, p = 0.035). Visualization using the cubic spline technique showed maximum survival at intermediate parasite intensities. CONCLUSIONS/SIGNIFICANCE: Our results indicate that failing to recognize the potential for a non-linear relationship between parasite infection intensity and host fitness may lead to the potentially erroneous conclusion that the parasite is harmless to its host. Here we show that high parasite intensities indeed reduced survival, but this effect was masked by reduced survival for birds heavily suppressing their parasite intensities. Reduced survival among hosts with low parasite intensities suggests costs of controlling parasite infections; however, the nature of such costs remains to be elucidated.
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35.
  • Stjernman, Martin, et al. (författare)
  • Survival costs of reproduction in the blue tit (Parus caeruleus): a role for blood parasites?
  • 2004
  • Ingår i: Royal Society of London. Proceedings B. Biological Sciences. - : The Royal Society. - 1471-2954. ; 271:1555, s. 2387-2394
  • Tidskriftsartikel (refereegranskat)abstract
    • One of the central tenets in life-history theory is that there is a trade-off between current and future reproduction (i.e. a cost of reproduction). The mechanism for this cost of reproduction is, however, largely unknown. One hypothesis is that the high workload during reproduction compromises resistance to parasites and that the resulting increase in parasitaemia has negative effects on the prospects of future survival. Although empirical evidence for a negative relationship between reproductive effort and parasite resistance exists, the causal relationships between reproductive effort, parasite resistance and future reproduction are still unclear. We use a path analytical approach to investigate whether a change in parasite resistance (as measured by intensities of infections by the blood parasite Haemoproteus) after manipulation of reproductive effort, translates into altered survival in female blue tits. Our results show a negative relationship between reproductive effort and parasite resistance, although evident only in first-year breeders. Moreover, we found survival costs of reproduction in first-year breeders. These costs were, however, not mediated by the blood parasite studied.
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36.
  • Tälle, Malin, et al. (författare)
  • Land sharing complements land sparing in the conservation of disturbance-dependent species
  • 2023
  • Ingår i: Ambio. - : Springer Science and Business Media LLC. - 0044-7447 .- 1654-7209. ; 52:3, s. 571-584
  • Forskningsöversikt (refereegranskat)abstract
    • Alteration of natural disturbances in human-modified landscapes has resulted in many disturbance-dependent species becoming rare. Conservation of such species requires efforts to maintain or recreate disturbance regimes. We compared benefits of confining efforts to habitats in protected areas (a form of land sparing) versus integrating them with general management of production land (a form of land sharing), using two examples: fire in forests and grazing in semi-natural grasslands. We reviewed empirical studies from the temperate northern hemisphere assessing effects of disturbances in protected and non-protected areas, and compiled information from organisations governing and implementing disturbances in Sweden. We found advantages with protection of areas related to temporal continuity and quality of disturbances, but the spatial extent of disturbances is higher on production land. This suggests that an approach where land sparing is complemented with land sharing will be most effective for preservation of disturbance-dependent species in forests and semi-natural grasslands.
  •  
37.
  • Vale, P. F., et al. (författare)
  • Temperature-dependent costs of parasitism and maintenance of polymorphism under genotype-by-environment interactions
  • 2008
  • Ingår i: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 21:5, s. 1418-1427
  • Tidskriftsartikel (refereegranskat)abstract
    • The maintenance of genetic variation for infection-related traits is often attributed to coevolution between hosts and parasites, but it can also be maintained by environmental variation if the relative fitness of different genotypes changes with environmental variation. To gain insight into how infection-related traits are sensitive to environmental variation, we exposed a single host genotype of the freshwater crustacean Daphnia magna to four parasite isolates (which we assume to represent different genotypes) of its naturally co-occurring parasite Pasteuria ramosa at 15, 20 and 25 degrees C. We found that the cost to the host of becoming infected varied with temperature, but the magnitude of this cost did not depend on the parasite isolate. Temperature influenced parasite fitness traits; we found parasite genotype-by-environment (G x E) interactions for parasite transmission stage production, suggesting the potential for temperature variation to maintain genetic variation in this trait. Finally, we tested for temperature-dependent relationships between host and parasite fitness traits that form a key component of models of virulence evolution, and we found them to be stable across temperatures.
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38.
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39.
  • Westerdahl, Helena, et al. (författare)
  • MHC-I Affects Infection Intensity but Not Infection Status with a Frequent Avian Malaria Parasite in Blue Tits
  • 2013
  • Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8:8
  • Tidskriftsartikel (refereegranskat)abstract
    • Host resistance against parasites depends on three aspects: the ability to prevent, control and clear infections. In vertebrates the immune system consists of innate and adaptive immunity. Innate immunity is particularly important for preventing infection and eradicating established infections at an early stage while adaptive immunity is slow, but powerful, and essential for controlling infection intensities and eventually clearing infections. Major Histocompatibility Complex (MHC) molecules are central in adaptive immunity, and studies on parasite resistance and MHC in wild animals have found effects on both infection intensity (parasite load) and infection status (infected or not). It seems MHC can affect both the ability to control infection intensities and the ability to clear infections. However, these two aspects have rarely been considered simultaneously, and their relative importance in natural populations is therefore unclear. Here we investigate if MHC class I genotype affects infection intensity and infection status with a frequent avian malaria infection Haemoproteus majoris in a natural population of blue tits Cyanistes caeruleus. We found a significant negative association between a single MHC allele and infection intensity but no association with infection status. Blue tits that carry a specific MHC allele seem able to suppress H. majoris infection intensity, while we have no evidence that this allele also has an effect on clearance of the H. majoris infection, a result that is in contrast with some previous studies of MHC and avian malaria. A likely explanation could be that the clearance rate of avian malaria parasites differs between avian malaria lineages and/or between avian hosts.
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