Disentangling the impact of AM fungi versus roots on soil structure and water transport

Paul D. Hallett*, Debbie S. Feeney, A. Glyn Bengough, Matthias C. Rillig, Charlie M. Scrimgeour, Iain M. Young

*Corresponding author for this work

Research output: Contribution to journalArticle

112 Citations (Scopus)

Abstract

The relative importance of roots and AM-fungi on soil physical processes was investigated by controlling the presence of roots and AM fungi in pot experiments using a mycorrhiza-defective tomato mutant and a wild-type tomato (Solanum lycopersicum L.). Root-Zone and Bulk Soil sections were established by splitting pots into two lengthwise halves using a nylon mesh that contained roots whilst allowing the free movement of fungal hyphae. Post-incubation microbial populations and fungal biomass were measured and related to soil stability, pore structure and water repellency. Unplanted controls consistently had the least fungal biomass, fatty acids, water-stable aggregates (WSA) and water repellency. Wild-type-planted treatments had significantly more WSA than mycorrhiza-defective treatments (P < 0.01). Fluctuations in water content induced by transpiration caused significant changes in soil pore structure, measured using high-resolution X-Ray computer tomography. Porosity and mean pore size increased in soil aggregates from planted treatments, which had larger more heterogeneous pores than those in the unplanted soils. AM fungi accentuated soil stability. However, changes were not linked to repellency and fungal biomass. The presence of plants, regardless of AM fungi, appears to have the greatest impact on increasing soil stability.

Original languageEnglish
Pages (from-to)183-196
Number of pages14
JournalPlant and Soil
Volume314
Issue number1-2
Early online date26 Jul 2008
DOIs
Publication statusPublished - Jan 2009

Keywords

  • management
  • organic-matter
  • exopolysaccharide production
  • glomalin
  • arbuscular mycorrhizal fungi
  • water transport
  • colonization
  • microbial community dynamics
  • hyphae
  • AM Fungi
  • soil structure
  • x-ray computed tomography
  • polysaccharide
  • soil biota
  • aggregate stability
  • root zone

Cite this

Hallett, P. D., Feeney, D. S., Bengough, A. G., Rillig, M. C., Scrimgeour, C. M., & Young, I. M. (2009). Disentangling the impact of AM fungi versus roots on soil structure and water transport. Plant and Soil, 314(1-2), 183-196. https://doi.org/10.1007/s11104-008-9717-y