Arbuscular mycorrhizal fungal community composition is altered by long-term litter removal but not litter addition in a lowland tropical forest

Research output: Contribution to journalArticle

Abstract

Tropical forest productivity is sustained by the cycling of nutrients through decomposing organic matter. Arbuscular mycorrhizal (AM) fungi play a key role in the nutrition of tropical trees, yet there has been little experimental investigation into the role of AM fungi in nutrient cycling via decomposing organic material in tropical forests. We evaluated the responses of AM fungi in a long-term leaf litter addition and removal experiment in a tropical forest in Panama. We described AM fungal communities using 454-pyrosequencing, quantified the proportion of root length colonised by AM fungi using microscopy, and estimated AM fungal biomass using a lipid biomarker. AM fungal community composition was altered by litter removal but not litter addition. Root colonisation was substantially greater in the superficial organic layer compared with the mineral soil. Overall colonisation was lower in the litter removal treatment, which lacked an organic layer. There was no effect of litter manipulation on the concentration of the AM fungal lipid biomarker in the mineral soil. We hypothesise that reductions in organic matter brought about by litter removal may lead to AM fungi obtaining nutrients from recalcitrant organic or mineral sources in the soil, besides increasing fungal competition for progressively limited resources.

Details

Authors
Organisations
External organisations
  • Washington University in St. Louis
  • University of Cambridge
  • Smithsonian Tropical Research Institute
  • Northern Arizona University
  • Lancaster University
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Botany

Keywords

  • 454-sequencing, Arbuscular mycorrhizal (AM) fungi, Litterfall, Nutrient cycling, Organic matter, Tropical forest
Original languageEnglish
Pages (from-to)455-467
JournalNew Phytologist
Volume214
Issue number1
Early online date2017
Publication statusPublished - 2017 Apr
Publication categoryResearch
Peer-reviewedYes