Production and turnover of ectomycorrhizal extramatrical mycelial biomass and necromass under elevated CO2 and nitrogen fertilization.

Journal Article

Extramatrical mycelia (EMM) of ectomycorrhizal fungi are important in carbon (C) and nitrogen (N) cycling in forests, but poor knowledge about EMM biomass and necromass turnovers makes the quantification of their role problematic. We studied the impacts of elevated CO2 and N fertilization on EMM production and turnover in a Pinus taeda forest. EMM C was determined by the analysis of ergosterol (biomass), chitin (total bio- and necromass) and total organic C (TOC) of sand-filled mycelium in-growth bags. The production and turnover of EMM bio- and necromass and total C were estimated by modelling. N fertilization reduced the standing EMM biomass C to 57% and its production to 51% of the control (from 238 to 122 kg C ha(-1)  yr(-1) ), whereas elevated CO2 had no detectable effects. Biomass turnover was high (˜13 yr(-1) ) and unchanged by the treatments. Necromass turnover was slow and was reduced from 1.5 yr(-1) in the control to 0.65 yr(-1) in the N-fertilized treatment. However, TOC data did not support an N effect on necromass turnover. An estimated EMM production ranging from 2.5 to 6% of net primary production stresses the importance of its inclusion in C models. A slow EMM necromass turnover indicates an importance in building up forest humus.

Full Text

Duke Authors

Cited Authors

  • Ekblad, A; Mikusinska, A; Ågren, GI; Menichetti, L; Wallander, H; Vilgalys, R; Bahr, A; Eriksson, U

Published Date

  • August 2016

Published In

Volume / Issue

  • 211 / 3

Start / End Page

  • 874 - 885

PubMed ID

  • 27118132

Electronic International Standard Serial Number (EISSN)

  • 1469-8137

International Standard Serial Number (ISSN)

  • 0028-646X

Digital Object Identifier (DOI)

  • 10.1111/nph.13961

Language

  • eng