CONFLICT IN UKRAINE: ASSESSING PHENOLOGICAL CHANGES IN GRAIN PRODUCTION AREAS OF UKRAINE DURING THE RUSSO-UKRAINIAN CONFLICT USING NDVI TIME SERIES DERIVED FROM SENTINEL-2 DATA

This study employs Sentinel-2 Level 2A satellite images, categorized as Analysis Ready Data (ARD), to investigate the impact of the Russia-Ukraine conflict on agriculture. The focus is on phenological changes in three designated zones. The eligibility criteria for the designated zones are determined by their proximity to the frontline, the significance of their agricultural sector, and the degree of direct impact experienced. These impacts encompass various factors such as city occupations, illegal annexation of territories, displacement of civilians, bombings, and international condemnations linked to these events. The processing flow involves the development of a QGIS model for automated operations, including NDVI calculation, image cropping, and statistical value computation. The widely used Normalized Difference Vegetation Index (NDVI) is calculated using the Raster calculator algorithm. Clipping operations are performed to focus on relevant areas, and statistical indicators are computed within each parcel using the Zonal statistics algorithm. Excel operations are then utilized for constructing NDVI time series, allowing for visual comparisons of crop behavior and subsequent clustering based on phenological patterns. The results reveal a general decrease in NDVI values across all zones after the conflict onset, indicating potential disruptions in vegetation development cycles. While the study provides valuable insights, future research should expand to a national level and incorporate higher-resolution satellite data and field verifications for enhanced robustness.