Mapping Vegetation Cover and Assessing Dune Stabilization in the Merzouga Desert Using NDVI Indicators from ASTER and Landsat Data

Authors

  • Naoual El Hammouch

    Geo-Resources and Environment Laboratory, Sidi Mohammed Ben Abdellah University, Fez 30000, Morocco
  • Hassan Tabyaoui

    Geo-Resources and Environment Laboratory, Sidi Mohammed Ben Abdellah University, Fez 30000, Morocco
  • Fatima El Hammichi

    Geo-Resources and Environment Laboratory, Sidi Mohammed Ben Abdellah University, Fez 30000, Morocco
  • Ahmed Gaber

    Faculty of Science, Port Said University, Port Said 42526, Egypt

DOI:

https://doi.org/10.30564/re.v8i3.12800
Received: 19 November 2025 | Revised: 6 January 2026 | Accepted: 20 January 2026 | Published Online: 18 May 2026

Abstract

Desertification and sand dune mobility constitute major environmental challenges in arid regions, particularly in the Merzouga Desert of southeastern Morocco. This study examines the role of vegetation in controlling dune dynamics through a combined analysis of multi-temporal remote sensing data and topographic change detection. Vegetation cover and spatial heterogeneity were evaluated using the Normalized Difference Vegetation Index (NDVI), while sand mobility was assessed using the Normalized Sand Index (NSI) derived from ASTER and Landsat 8 imagery. In addition, geomorphic changes between 2011 and 2025 were analyzed using a DEM of Difference based on ASTER GDEM and Sentinel 1-derived DEMs. The results demonstrate a consistent inverse relationship between vegetation cover and sand mobility across all periods. Vegetated areas, particularly along dune margins, interdune depressions, and oasis environments, are mainly associated with semi-stable dunes and reduced aeolian activity. Even sparse shrub patches significantly contribute to sand trapping and localized dune stabilization. Topographic analysis reveals moderate but spatially organized elevation changes, with sand accumulation on dune crests and windward slopes and erosion on leeward flanks, reflecting dominant regional wind regimes. Central dune fields show relative elevation stability, suggesting a dynamic equilibrium between erosion and deposition. Although classification accuracy decreases in 2025 due to spectral confusion in sparsely vegetated surfaces, qualitative validation using high-resolution Google Earth imagery confirms the reliability of the main spatial trends. Overall, the findings highlight strong vegetation and topography feedbacks that govern dune stabilization processes and provide valuable insights for ecological monitoring and sustainable land management in desert environments.

Keywords:

Vegetation Stabilization; Sand Dunes; NDVI; ASTER; Landsat; Desertification; Merzouga; Morocco

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How to Cite

El Hammouch, N., Tabyaoui, H., El Hammichi, F., & Gaber, A. (2026). Mapping Vegetation Cover and Assessing Dune Stabilization in the Merzouga Desert Using NDVI Indicators from ASTER and Landsat Data. Research in Ecology, 8(3), 136–152. https://doi.org/10.30564/re.v8i3.12800

Issue

Vol.8, Iss.3 (June 2026)(In Progress)

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Article

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Copyright © 2026 Naoual El Hammouch, Hassan Tabyaoui, Fatima El Hammichi, Ahmed Gaber

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This is an open access article under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) License.

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