MONITORING SOIL DEGRADATION IN SHIRAK REGION USING SENTINEL-2 SATELLITE DATA (2015–2025)

Abstract

The study was conducted to analyze the spatiotemporal dynamics of land degradation in the Shirak Region of Armenia for the period 2015–2025 using Sentinel-2 satellite imagery. The Normalized Difference Vegetation Index (NDVI) and the Soil Adjusted Vegetation Index (SAVI) were applied in the research. Analyses performed within the QGIS geographic information system environment indicate that vegetation dynamics exhibit an unstable nature. This suggests that annual fluctuations in the index values (NDVI, SAVI) are largely driven by quantitative changes in atmospheric precipitation (climatic factor) rather than stable qualitative soil improvement or degradation. The application of the SAVI index, through the integration of a specific soil brightness correction factor (L=0.5), allowed mitigating the background soil effect and obtaining more accurate data for sparsely vegetated areas. It was revealed that the Southwestern part of the region (Ani community) is the most vulnerable: the intensive erosion processes observed here correspond with consistently low SAVI values, indicating deep soil degradation trends.