Journal Article

Microbial succession on decomposing root litter in a drought-prone Scots pine forest

Rumpel, Cornelia, Stierli, Beat, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Herzog, Claude, Institut d'écologie et des sciences de l'environnement de Paris (iEES Paris) ; Institut National de la Recherche Agronomique (INRA)-Sorbonne Université (SU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Frey, Beat, Hartmann, Martin, Buchmann, Nina, Brunner, Ivano

2019

Overview

Decomposition is a major flux of the carbon cycle in forest soils and understanding the involved processes is a key for budgeting carbon turnover. Decomposition is constrained by the presence of biological agents such as microorganisms and the underlying environmental conditions such as water availability. A metabarcoding approach of ribosomal markers was chosen to study the succession of bacterial and fungal decomposers on root litter. Litterbags containing pine roots were buried in a pine forest for two years and sequentially sampled. Decomposition and the associated communities were surveyed under ambient dry and long-term irrigation conditions. Early decomposition stages were characterized by the presence of fast-cycling microorganisms such as Bacteroidetes and Helotiales, which were then replaced by more specialized bacteria and litter-associated or parasitic groups such as Acidobacteria, white rots, and Pleosporales. This succession was likely driven by a decrease of easily degradable carbohydrates and a relative increase in persistent compounds such as lignin. We hypothesize that functional redundancy among the resident microbial taxa caused similar root decomposition rates in control and irrigated forest soils. These findings have important implications for drought-prone Alpine forests as frequent drought events reduce litter fall, but not litter decomposition, potentially resulting in lower carbon stocks.

• Publisher: Nature Publishing Group,CCSD,Nature Publishing Group UK,Oxford University Press
• Subject: 631/158/855 / 704/158/2454 / 704/47 / Bacteria / Bacteria - classification / Bacteria - genetics / Bacteria - isolation & purification / Bacteria - metabolism / Biodiversity and Ecology / Biological weapons / Biomedical and Life Sciences / Carbohydrates / Carbon / Carbon - metabolism / Carbon Cycle / Coniferous forests / Decomposition / Drought / Droughts / Ecological succession / Ecology / Ecology, environment / Ecosystems / Environmental conditions / Environmental Sciences / Evolutionary Biology / Forest soils / Forests / Fungi - classification / Fungi - genetics / Fungi - isolation & purification / Fungi - metabolism / Life Sciences / Lignin / Litter / Litter fall / Microbial Ecology / Microbial Genetics and Genomics / Microbiology / Microbiology and Parasitology / Microorganisms / Pine / Pine trees / Pinus sylvestris - metabolism / Pinus sylvestris - microbiology / Plant Leaves - metabolism / Plant Leaves - microbiology / Redundancy / Soil Microbiology / Soils / Water availability