Showing papers by "Anders Dahlberg published in 2015"

Carbon sequestration is related to mycorrhizal fungal community shifts during long-term succession in boreal forests.

Abstract: Summary Boreal forest soils store a major proportion of the global terrestrial carbon (C) and below-ground inputs contribute as much as above-ground plant litter to the total C stored in the soil. A better understanding of the dynamics and drivers of root-associated fungal communities is essential to predict long-term soil C storage and climate feedbacks in northern ecosystems. We used 454-pyrosequencing to identify fungal communities across fine-scaled soil profiles in a 5000 yr fire-driven boreal forest chronosequence, with the aim of pinpointing shifts in fungal community composition that may underlie variation in below-ground C sequestration. In early successional-stage forests, higher abundance of cord-forming ectomycorrhizal fungi (such as Cortinarius and Suillus species) was linked to rapid turnover of mycelial biomass and necromass, efficient nitrogen (N) mobilization and low C sequestration. In late successional-stage forests, cord formers declined, while ericoid mycorrhizal ascomycetes continued to dominate, potentially facilitating long-term humus build-up through production of melanized hyphae that resist decomposition. Our results suggest that cord-forming ectomycorrhizal fungi and ericoid mycorrhizal fungi play opposing roles in below-ground C storage. We postulate that, by affecting turnover and decomposition of fungal tissues, mycorrhizal fungal identity and growth form are critical determinants of C and N sequestration in boreal forests.

A fungal perspective on conservation biology.

Abstract: Hitherto fungi have rarely been considered in conservation biology, but this is changing as the field moves from addressing single species issues to an integrative ecosystem-based approach. The current emphasis on biodiversity as a provider of ecosystem services throws the spotlight on the vast diversity of fungi, their crucial roles in terrestrial ecosystems, and the benefits of considering fungi in concert with animals and plants. We reviewed the role of fungi in ecosystems and composed an overview of the current state of conservation of fungi. There are 5 areas in which fungi can be readily integrated into conservation: as providers of habitats and processes important for other organisms; as indicators of desired or undesired trends in ecosystem functioning; as indicators of habitats of conservation value; as providers of powerful links between human societies and the natural world because of their value as food, medicine, and biotechnological tools; and as sources of novel tools and approaches for conservation of megadiverse organism groups. We hope conservation professionals will value the potential of fungi, engage mycologists in their work, and appreciate the crucial role of fungi in nature.

Tillstånd och trender för arter och deras livsmiljöer

Abstract: 2015 ars upplaga av den svenska rodlistan ar den fjarde i ordningen. Den ar baserad pa IUCN:s rodlistningskriterier och revideras vart femte ar. I rodlistan bedoms risken som enskilda arter av djur, vaxter och svampar loper att forsvinna fran Sverige. Bedomningen utfors av ArtDatabankens medarbetare i samverkan med over 100 externa experter, indelade i 14 expertkommitteer for olika organismgrupper. Under arbetet med 2015 ars rodlista har tillstand och trender bedomts for 21 600 arter och 1 318 lagre taxa (apomiktiska arter, underarter och varieteter), sammanlagt ca 22 900 taxa. Av de bedomda arterna klassificerades 2 029 som hotade (kategorierna CR, EN och VU) och 4 273 som rodlistade (inkluderar aven kategorierna NT, RE och DD). Forhallandet mellan antalet rodlistade och antalet bedomda arter ar 19,8 %, vilket ar ungefar samma varde som 2010 och 2005. I denna rapport jamfors antalet och andelen rodlistade arter mellan olika organismgrupper, biotoper, substrat och paverkansfaktorer. Texten ar indelad i en allman del och atta kapitel inriktade pa olika landskapstyper. Landskapstyperna utgor en grov indelning av landets miljoer enligt foljande kategorier: Skog, Jordbrukslandskap, Urbana miljoer, Fjall, Vatmarker, Sotvatten, Havsstrander och Havsmiljoer. Skogen och jordbrukslandskapet ar de artrikaste landskapstyperna med 1 800 respektive 1 400 arter som har en stark anknytning dit, och ytterligare flera hundra arter som forekommer dar mer sporadiskt. De faktorer som paverkar flest rodlistade arter i Sverige ar skogsavverkning och igenvaxning, som bada utgor ett hot mot vardera ca 30 % av de rodlistade arterna. Avverkning minskar arealen av skog dar naturliga strukturer och naturlig dynamik uppratthalls, och den orsakar darmed forlust av livsmiljoer. Igenvaxning orsakas av ett antal faktorer, bland annat upphorande havd (bete och slatter), godsling, tradplantering och brist pa naturliga storningsregimer som t.ex. regelbundna oversvamningar kring vattendrag och sjoar. Andra viktiga paverkansfaktorer ar fiske, torrlaggning av vatmarker, tillbakagang hos vardarter (framst alm och ask som drabbats av invasiva svampsjukdomar), klimatforandringar och konkurrens fran invasiva arter. IUCN:s rodlisteindex beraknas for ett urval av de bedomda organismgrupperna. Rodlisteindex visar att skillnaderna mellan rodlistorna fran 2000, 2005, 2010 och 2015 ar sma. Ett par undantag finns dock. Groddjur och stora daggdjur har fatt en nagot forbattrad situation sedan 2000. Totalt forefaller det anda som att trycket mot Sveriges artstock har forblivit relativt konstant under de senaste 15 aren.