Skip to main content

Long-term effects of grazing and topography on extra-radical hyphae of arbuscular mycorrhizal fungi in semi-arid grasslands


Grazing and topography have drastic effects on plant communities and soil properties. These effects are thought to influence arbuscular mycorrhizal (AM) fungi. However, the simultaneous impacts of grazing pressure (sheep ha−1) and topography on plant and soil factors and their relationship to the production of extra-radical AM hyphae are not well understood. Our 10-year study assessed relationships between grazing, plant species richness, aboveground plant productivity, soil nutrients, edaphic properties, and AM hyphal length density (HLD) in different topographic areas (flat or sloped). We found HLD linearly declined with increasing grazing pressure (1.5–9.0 sheep ha−1) in sloped areas, but HLD was greatest at moderate grazing pressure (4.5 sheep ha−1) in flat areas. Structural equation modeling indicates grazing reduces HLD by altering soil nutrient dynamics in sloped areas, but non-linearly influences HLD through plant community and edaphic changes in flat areas. Our findings highlight how topography influences key plant and soil factors, thus regulating the effects of grazing pressure on extra-radical hyphal production of AM fungi in grasslands. Understanding how grazing and topography influence AM fungi in semi-arid grasslands is vital, as globally, severe human population pressure and increasing demand for food aggravate the grazing intensity in grasslands.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6


Download references


We are grateful to all the people who helped collect and process data over the years.


This project was supported by National Natural Science Foundation of China (31501996) and (31700389), Basic research program of Jiangsu province (Natural Science Foundation)-Youth Foundation (BK20160738) and (BK20150665). We acknowledge the Inner Mongolia Grassland Ecosystem Research Station (IMGERS) of the Chinese Academy of Sciences for providing field facilities and a long-term meteorological dataset.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Gaowen Yang.

Electronic supplementary material


(DOCX 466 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Ren, H., Gui, W., Bai, Y. et al. Long-term effects of grazing and topography on extra-radical hyphae of arbuscular mycorrhizal fungi in semi-arid grasslands. Mycorrhiza 28, 117–127 (2018).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:


  • Grazing pressure
  • Hyphal length density
  • Sheep
  • Edaphic properties
  • Structural equation modeling