Log in

Effects of freeze-thaw cycles on soil macropores and its implications on formation of hummocks in alpine meadows in the Qinghai Lake watershed, northeastern Qinghai-Tibet Plateau

  • Soils, Sec 3 • Remediation and Management of Contaminated or Degraded Lands • Research Article
  • Published:
Journal of Soils and Sediments Aims and scope Submit manuscript

Abstract

Purpose

The alpine regions are characterized by frequent freeze-thaw cycles, which influence the soil structure remarkably. However, the effects of freeze-thaw cycles on the soil macropore structure and its implications on the formation of hummocks are not well understood. This study aims to quantify the soil macropores of hummocks and the effects of freeze-thaw cycles on soil macropores to reveal its implications on the formation of hummocks in alpine meadows.

Materials and methods

A total of nine intact soil columns (0–50 cm deep) were excavated from the alpine meadows. Three replicates were collected from the hummocks and three were collected from the interhummocks, and they were scanned by X-ray computed tomography (CT). Another three replicates were excavated from the adjacent non-hummock alpine meadows, which were subjected to successive freeze-thaw cycles (0, 1, 3, and 6) and then scanned using X-ray CT.

Results and discussion

Soil macropore network of hummocks was more extensive and continuous than that of the interhummocks. The volumetric distribution of soil macropores in hummocks was multiple, while soil macropores of the interhummocks intensively fell in the volume range of 0–400 mm3. The soil macroporosity, macropore number density, surface area density, length density, node density, branch density, and mean macropore size of the hummocks were several times higher than those of the interhummocks. These soil macropore parameters showed a decrease after the first and third freeze-thaw cycle and later increased through the next three cycles. Soil macropores with volume > 1000 mm3 transformed into smaller ones (600–1000 mm3) during the freeze-thaw process.

Conclusions

The soil macropore patterns of hummocks and interhummocks differed distinctly. Soil macropores responded significantly to freeze-thaw cycles. The effects of freeze-thaw cycles on the macropore number and size were more significant than on the morphology in alpine meadows. Hummock formation is closely related to the soil macropores during the freeze-thaw cycles, and the soil moisture played a crucial role in the hummock formation process.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
EUR 32.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or Ebook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9

Similar content being viewed by others

References

Download references

Acknowledgments

Our deepest gratitude goes to the editors and anonymous reviewers for their careful work and constructive suggestions that help improve this paper substantially.

Funding

This study was financially supported by the National Science Foundation of China (Grant Numbers: 41971053 & 41730854).

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to **a Hu.

Additional information

Responsible editor: Claudio Colombo

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Gao, Z., Hu, X., Li, XY. et al. Effects of freeze-thaw cycles on soil macropores and its implications on formation of hummocks in alpine meadows in the Qinghai Lake watershed, northeastern Qinghai-Tibet Plateau. J Soils Sediments 21, 245–256 (2021). https://doi.org/10.1007/s11368-020-02765-2

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11368-020-02765-2

Keywords

Navigation