Features of the humification process in soils of Thala Hills, Enderby land, East Antarctica: Insights from 13C-NMR spectroscopy

Ivan Alekseev; Elena Grek

doi:10.18393/ejss.1834403

Features of the humification process in soils of Thala Hills, Enderby land, East Antarctica: Insights from 13C-NMR spectroscopy

Abstract

In East Antarctica, ice-free areas (oases) exhibit a wide range of environmental conditions that influence soil development. Exploring the interactions between biological and abiotic factors, along with the composition and behavior of soil organic matter, offers valuable insights into how Antarctic ecosystems react to environmental stresses. This study examined the biogeochemical characteristics and molecular composition of soil organic matter in Cryosols of the Thala Hills oasis, Enderby Land, East Antarctica. The soils studied are generally shallow, with mostly coarse textures, slightly acidic to near-neutral pH levels (from 5.40 to 6.87), and very low organic carbon content in most of the samples (TOC<1%). We used 13C CPMAS NMR spectroscopy spectroscopy to evaluate the molecular composition of humic substances extracted from typical Leptic (Lithic) Cryosol and from an ornithogenic Cryosol. Significant peaks associated with carboxylic acids (170-190 ppm) indicated that organic matter transformation processes are influenced by vegetation cover, particularly moss-lichen communities. Humification processes were observed to be more pronounced in ornithogenic soils, as indicated by the formation of humic acids with a more developed peripheral aliphatic component (outer-chain aliphatic moieties) and higher sp²/sp³ carbon ratio. These ratios indicate a balance between aliphatic content—suggesting potential for decomposition—and aromatic structures that contribute to long-term stability.

Keywords

Supporting Institution

Russian Science Foundation

Project Number

24-27-00361

Thanks

The research was supported by Russian Science Foundation (Project № 24-27-00361 «Soils in Eastern Antarctica oases: biogeochemistry, stability of organic matter and environmental risks») and within the framework of the Karelian Research Centre RAS research task № FMEN-2025-0002. The Authors would like to acknowledge Russian Antarctic Expedition, colleagues for their crucial help in fieldwork.

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Details

Primary Language

English

Subjects

Soil Sciences and Plant Nutrition (Other)

Journal Section

Research Article

Authors

Ivan Alekseev ^* This is me
0000-0002-0512-3849
Russian Federation

Elena Grek This is me
0000-0002-5515-4686
Russian Federation

Publication Date

January 2, 2026

Submission Date

June 27, 2025

Acceptance Date

November 26, 2025

Published in Issue

Year 2026 Volume: 15 Number: 1

DOI

https://doi.org/10.18393/ejss.1834403

IZ

https://izlik.org/JA78LP48PL

Cite

RIS / Bibtex

APA

Alekseev, I., & Grek, E. (2026). Features of the humification process in soils of Thala Hills, Enderby land, East Antarctica: Insights from 13C-NMR spectroscopy. Eurasian Journal of Soil Science, 15(1), 102-112. https://doi.org/10.18393/ejss.1834403

AMA

1.Alekseev I, Grek E. Features of the humification process in soils of Thala Hills, Enderby land, East Antarctica: Insights from 13C-NMR spectroscopy. EJSS. 2026;15(1):102-112. doi:10.18393/ejss.1834403

Chicago

Alekseev, Ivan, and Elena Grek. 2026. “Features of the Humification Process in Soils of Thala Hills, Enderby Land, East Antarctica: Insights from 13C-NMR Spectroscopy”. Eurasian Journal of Soil Science 15 (1): 102-12. https://doi.org/10.18393/ejss.1834403.

EndNote

Alekseev I, Grek E (January 1, 2026) Features of the humification process in soils of Thala Hills, Enderby land, East Antarctica: Insights from 13C-NMR spectroscopy. Eurasian Journal of Soil Science 15 1 102–112.

IEEE

[1]I. Alekseev and E. Grek, “Features of the humification process in soils of Thala Hills, Enderby land, East Antarctica: Insights from 13C-NMR spectroscopy”, EJSS, vol. 15, no. 1, pp. 102–112, Jan. 2026, doi: 10.18393/ejss.1834403.

ISNAD

Alekseev, Ivan - Grek, Elena. “Features of the Humification Process in Soils of Thala Hills, Enderby Land, East Antarctica: Insights from 13C-NMR Spectroscopy”. Eurasian Journal of Soil Science 15/1 (January 1, 2026): 102-112. https://doi.org/10.18393/ejss.1834403.

JAMA

1.Alekseev I, Grek E. Features of the humification process in soils of Thala Hills, Enderby land, East Antarctica: Insights from 13C-NMR spectroscopy. EJSS. 2026;15:102–112.

MLA

Alekseev, Ivan, and Elena Grek. “Features of the Humification Process in Soils of Thala Hills, Enderby Land, East Antarctica: Insights from 13C-NMR Spectroscopy”. Eurasian Journal of Soil Science, vol. 15, no. 1, Jan. 2026, pp. 102-1, doi:10.18393/ejss.1834403.

Vancouver

1.Ivan Alekseev, Elena Grek. Features of the humification process in soils of Thala Hills, Enderby land, East Antarctica: Insights from 13C-NMR spectroscopy. EJSS. 2026 Jan. 1;15(1):102-1. doi:10.18393/ejss.1834403