Arbuscular mycorrhizal fungi effect on the hydrological regime in vegetated soil

Roberts-Self, Eve G. and Tarantino, Alessandro (2026) Arbuscular mycorrhizal fungi effect on the hydrological regime in vegetated soil. Géotechnique. ISSN 0016-8505 (In Press)

[thumbnail of Roberts-Self-Tarantino-Geotechnique-2026-Arbuscular-mycorrhizal-fungi-effect-on-the-hydrological-regime-in-vegetated-soil] Text. Filename: Roberts-Self-Tarantino-Geotechnique-2026-Arbuscular-mycorrhizal-fungi-effect-on-the-hydrological-regime-in-vegetated-soil.pdf
Accepted Author Manuscript
Restricted to Repository staff only until 1 January 2099.

Download (8MB) | Request a copy

Abstract

Arbuscular mycorrhizal fungi (AMF) are increasingly used as biofertilizers in agriculture and being implemented in geotechnical engineering to establish vegetation on slopes. It is therefore crucial to understand the geotechnical consequences of AMF inoculation on water removal and retention and, hence, on stability of embankments and cut slopes. A first series of laboratory experiments involved planting Medicago sativa or Lolium perenne in mini-lysimeters, either inoculated with Rhizophagus irregularis or Funneliformis mosseae, or left uninoculated, and the monitoring of transpiration rates. A second series only involved M. sativa with monitoring of transpiration rates plus pore-water pressure and soil water content. AMF inoculation in M. sativa in the first experiment increased potential transpiration by over 55% due to increased shoot biomass but produced no effect in the second experiment despite similar AMF colonization. This was attributed to nutrient scarcity in the first experiment that possibly promoted fungal growth to scavenge nutrients in soil pores not accessible to roots. AMF inoculation did not significantly affect L. perenne transpiration possibly because AMF did not offer competitive advantages compared to the fine fibrous roots. No differences were observed in water-limited transpiration, consistent with no changes in water retention behaviour observed at low degrees of saturation.

ORCID iDs

Roberts-Self, Eve G. and Tarantino, Alessandro ORCID logoORCID: https://orcid.org/0000-0001-6690-748X;